/*------------------------------------------------------------------------- * * analyze.c * transform the parse tree into a query tree * * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * $Header: /cvsroot/pgsql/src/backend/parser/analyze.c,v 1.240 2002/08/02 18:15:06 tgl Exp $ * *------------------------------------------------------------------------- */ #include "postgres.h" #include "access/heapam.h" #include "catalog/catname.h" #include "catalog/heap.h" #include "catalog/index.h" #include "catalog/namespace.h" #include "catalog/pg_index.h" #include "catalog/pg_type.h" #include "nodes/makefuncs.h" #include "parser/analyze.h" #include "parser/gramparse.h" #include "parser/parsetree.h" #include "parser/parse_agg.h" #include "parser/parse_clause.h" #include "parser/parse_coerce.h" #include "parser/parse_expr.h" #include "parser/parse_oper.h" #include "parser/parse_relation.h" #include "parser/parse_target.h" #include "parser/parse_type.h" #include "parser/parse_expr.h" #include "rewrite/rewriteManip.h" #include "utils/builtins.h" #include "utils/fmgroids.h" #include "utils/lsyscache.h" #include "utils/relcache.h" #include "utils/syscache.h" #ifdef MULTIBYTE #include "mb/pg_wchar.h" #endif /* State shared by transformCreateSchemaStmt and its subroutines */ typedef struct { const char *stmtType; /* "CREATE SCHEMA" or "ALTER SCHEMA" */ char *schemaname; /* name of schema */ char *authid; /* owner of schema */ List *tables; /* CREATE TABLE items */ List *views; /* CREATE VIEW items */ List *grants; /* GRANT items */ List *fwconstraints; /* Forward referencing FOREIGN KEY constraints */ List *alters; /* Generated ALTER items (from the above) */ List *ixconstraints; /* index-creating constraints */ List *blist; /* "before list" of things to do before * creating the schema */ List *alist; /* "after list" of things to do after * creating the schema */ } CreateSchemaStmtContext; /* State shared by transformCreateStmt and its subroutines */ typedef struct { const char *stmtType; /* "CREATE TABLE" or "ALTER TABLE" */ RangeVar *relation; /* relation to create */ List *inhRelations; /* relations to inherit from */ bool hasoids; /* does relation have an OID column? */ Oid relOid; /* OID of table, if ALTER TABLE case */ List *columns; /* ColumnDef items */ List *ckconstraints; /* CHECK constraints */ List *fkconstraints; /* FOREIGN KEY constraints */ List *ixconstraints; /* index-creating constraints */ List *blist; /* "before list" of things to do before * creating the table */ List *alist; /* "after list" of things to do after * creating the table */ IndexStmt *pkey; /* PRIMARY KEY index, if any */ } CreateStmtContext; static Query *transformStmt(ParseState *pstate, Node *stmt, List **extras_before, List **extras_after); static Query *transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt); static Query *transformInsertStmt(ParseState *pstate, InsertStmt *stmt, List **extras_before, List **extras_after); static Query *transformIndexStmt(ParseState *pstate, IndexStmt *stmt); static Query *transformRuleStmt(ParseState *query, RuleStmt *stmt, List **extras_before, List **extras_after); static Query *transformSelectStmt(ParseState *pstate, SelectStmt *stmt); static Query *transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt); static Node *transformSetOperationTree(ParseState *pstate, SelectStmt *stmt); static Query *transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt); static Query *transformCreateStmt(ParseState *pstate, CreateStmt *stmt, List **extras_before, List **extras_after); static Query *transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt, List **extras_before, List **extras_after); static void transformColumnDefinition(ParseState *pstate, CreateStmtContext *cxt, ColumnDef *column); static void transformTableConstraint(ParseState *pstate, CreateStmtContext *cxt, Constraint *constraint); static void transformIndexConstraints(ParseState *pstate, CreateStmtContext *cxt); static void transformFKConstraints(ParseState *pstate, CreateStmtContext *cxt); static void applyColumnNames(List *dst, List *src); static List *getSetColTypes(ParseState *pstate, Node *node); static void transformForUpdate(Query *qry, List *forUpdate); static void transformConstraintAttrs(List *constraintList); static void transformColumnType(ParseState *pstate, ColumnDef *column); static void transformFkeyCheckAttrs(FkConstraint *fkconstraint, Oid *pktypoid); static void transformFkeyGetPrimaryKey(FkConstraint *fkconstraint, Oid *pktypoid); static bool relationHasPrimaryKey(Oid relationOid); static Oid transformFkeyGetColType(CreateStmtContext *cxt, char *colname); static void release_pstate_resources(ParseState *pstate); static FromExpr *makeFromExpr(List *fromlist, Node *quals); /* * parse_analyze - * analyze a raw parse tree and transform it to Query form. * * The result is a List of Query nodes (we need a list since some commands * produce multiple Queries). Optimizable statements require considerable * transformation, while many utility-type statements are simply hung off * a dummy CMD_UTILITY Query node. */ List * parse_analyze(Node *parseTree, ParseState *parentParseState) { List *result = NIL; ParseState *pstate = make_parsestate(parentParseState); /* Lists to return extra commands from transformation */ List *extras_before = NIL; List *extras_after = NIL; Query *query; List *listscan; query = transformStmt(pstate, parseTree, &extras_before, &extras_after); release_pstate_resources(pstate); while (extras_before != NIL) { result = nconc(result, parse_analyze(lfirst(extras_before), pstate)); extras_before = lnext(extras_before); } result = lappend(result, query); while (extras_after != NIL) { result = nconc(result, parse_analyze(lfirst(extras_after), pstate)); extras_after = lnext(extras_after); } /* * Make sure that only the original query is marked original. * We have to do this explicitly since recursive calls of parse_analyze * will have set originalQuery in some of the added-on queries. */ foreach(listscan, result) { Query *q = lfirst(listscan); q->originalQuery = (q == query); } pfree(pstate); return result; } static void release_pstate_resources(ParseState *pstate) { if (pstate->p_target_relation != NULL) heap_close(pstate->p_target_relation, NoLock); pstate->p_target_relation = NULL; pstate->p_target_rangetblentry = NULL; } /* * transformStmt - * transform a Parse tree into a Query tree. */ static Query * transformStmt(ParseState *pstate, Node *parseTree, List **extras_before, List **extras_after) { Query *result = NULL; switch (nodeTag(parseTree)) { /* * Non-optimizable statements */ case T_CreateStmt: result = transformCreateStmt(pstate, (CreateStmt *) parseTree, extras_before, extras_after); break; case T_IndexStmt: result = transformIndexStmt(pstate, (IndexStmt *) parseTree); break; case T_RuleStmt: result = transformRuleStmt(pstate, (RuleStmt *) parseTree, extras_before, extras_after); break; case T_ViewStmt: { ViewStmt *n = (ViewStmt *) parseTree; n->query = transformStmt(pstate, (Node *) n->query, extras_before, extras_after); /* * If a list of column names was given, run through and * insert these into the actual query tree. - thomas * 2000-03-08 * * Outer loop is over targetlist to make it easier to skip * junk targetlist entries. */ if (n->aliases != NIL) { List *aliaslist = n->aliases; List *targetList; foreach(targetList, n->query->targetList) { TargetEntry *te = (TargetEntry *) lfirst(targetList); Resdom *rd; Ident *id; Assert(IsA(te, TargetEntry)); rd = te->resdom; Assert(IsA(rd, Resdom)); if (rd->resjunk) /* junk columns don't get * aliases */ continue; id = (Ident *) lfirst(aliaslist); Assert(IsA(id, Ident)); rd->resname = pstrdup(id->name); aliaslist = lnext(aliaslist); if (aliaslist == NIL) break; /* done assigning aliases */ } if (aliaslist != NIL) elog(ERROR, "CREATE VIEW specifies more column names than columns"); } result = makeNode(Query); result->commandType = CMD_UTILITY; result->utilityStmt = (Node *) n; } break; case T_ExplainStmt: { ExplainStmt *n = (ExplainStmt *) parseTree; result = makeNode(Query); result->commandType = CMD_UTILITY; n->query = transformStmt(pstate, (Node *) n->query, extras_before, extras_after); result->utilityStmt = (Node *) parseTree; } break; case T_AlterTableStmt: result = transformAlterTableStmt(pstate, (AlterTableStmt *) parseTree, extras_before, extras_after); break; /* * Optimizable statements */ case T_InsertStmt: result = transformInsertStmt(pstate, (InsertStmt *) parseTree, extras_before, extras_after); break; case T_DeleteStmt: result = transformDeleteStmt(pstate, (DeleteStmt *) parseTree); break; case T_UpdateStmt: result = transformUpdateStmt(pstate, (UpdateStmt *) parseTree); break; case T_SelectStmt: if (((SelectStmt *) parseTree)->op == SETOP_NONE) result = transformSelectStmt(pstate, (SelectStmt *) parseTree); else result = transformSetOperationStmt(pstate, (SelectStmt *) parseTree); break; default: /* * other statements don't require any transformation-- just * return the original parsetree, yea! */ result = makeNode(Query); result->commandType = CMD_UTILITY; result->utilityStmt = (Node *) parseTree; break; } return result; } /* * transformDeleteStmt - * transforms a Delete Statement */ static Query * transformDeleteStmt(ParseState *pstate, DeleteStmt *stmt) { Query *qry = makeNode(Query); Node *qual; qry->commandType = CMD_DELETE; /* set up range table with just the result rel */ qry->resultRelation = setTargetTable(pstate, stmt->relation, interpretInhOption(stmt->relation->inhOpt), true); qry->distinctClause = NIL; /* fix where clause */ qual = transformWhereClause(pstate, stmt->whereClause); /* done building the range table and jointree */ qry->rtable = pstate->p_rtable; qry->jointree = makeFromExpr(pstate->p_joinlist, qual); qry->hasSubLinks = pstate->p_hasSubLinks; qry->hasAggs = pstate->p_hasAggs; if (pstate->p_hasAggs) parseCheckAggregates(pstate, qry, qual); return qry; } /* * transformInsertStmt - * transform an Insert Statement */ static Query * transformInsertStmt(ParseState *pstate, InsertStmt *stmt, List **extras_before, List **extras_after) { Query *qry = makeNode(Query); List *sub_rtable; List *sub_namespace; List *icolumns; List *attrnos; List *attnos; List *tl; qry->commandType = CMD_INSERT; pstate->p_is_insert = true; /* * If a non-nil rangetable/namespace was passed in, and we are doing * INSERT/SELECT, arrange to pass the rangetable/namespace down to the * SELECT. This can only happen if we are inside a CREATE RULE, and * in that case we want the rule's OLD and NEW rtable entries to * appear as part of the SELECT's rtable, not as outer references for * it. (Kluge!) The SELECT's joinlist is not affected however. We * must do this before adding the target table to the INSERT's rtable. */ if (stmt->selectStmt) { sub_rtable = pstate->p_rtable; pstate->p_rtable = NIL; sub_namespace = pstate->p_namespace; pstate->p_namespace = NIL; } else { sub_rtable = NIL; /* not used, but keep compiler quiet */ sub_namespace = NIL; } /* * Must get write lock on INSERT target table before scanning SELECT, * else we will grab the wrong kind of initial lock if the target * table is also mentioned in the SELECT part. Note that the target * table is not added to the joinlist or namespace. */ qry->resultRelation = setTargetTable(pstate, stmt->relation, false, false); /* * Is it INSERT ... SELECT or INSERT ... VALUES? */ if (stmt->selectStmt) { ParseState *sub_pstate = make_parsestate(pstate->parentParseState); Query *selectQuery; RangeTblEntry *rte; RangeTblRef *rtr; /* * Process the source SELECT. * * It is important that this be handled just like a standalone * SELECT; otherwise the behavior of SELECT within INSERT might be * different from a stand-alone SELECT. (Indeed, Postgres up * through 6.5 had bugs of just that nature...) */ sub_pstate->p_rtable = sub_rtable; sub_pstate->p_namespace = sub_namespace; /* * Note: we are not expecting that extras_before and extras_after * are going to be used by the transformation of the SELECT statement. */ selectQuery = transformStmt(sub_pstate, stmt->selectStmt, extras_before, extras_after); release_pstate_resources(sub_pstate); pfree(sub_pstate); Assert(IsA(selectQuery, Query)); Assert(selectQuery->commandType == CMD_SELECT); if (selectQuery->into || selectQuery->isPortal) elog(ERROR, "INSERT ... SELECT may not specify INTO"); /* * Make the source be a subquery in the INSERT's rangetable, and * add it to the INSERT's joinlist. */ rte = addRangeTableEntryForSubquery(pstate, selectQuery, makeAlias("*SELECT*", NIL), true); rtr = makeNode(RangeTblRef); /* assume new rte is at end */ rtr->rtindex = length(pstate->p_rtable); Assert(rte == rt_fetch(rtr->rtindex, pstate->p_rtable)); pstate->p_joinlist = lappend(pstate->p_joinlist, rtr); /* * Generate a targetlist for the INSERT that selects all the * non-resjunk columns from the subquery. (We need this to be * separate from the subquery's tlist because we may add columns, * insert datatype coercions, etc.) * * HACK: constants in the INSERT's targetlist are copied up as-is * rather than being referenced as subquery outputs. This is * mainly to ensure that when we try to coerce them to the target * column's datatype, the right things happen for UNKNOWN * constants. Otherwise this fails: INSERT INTO foo SELECT 'bar', * ... FROM baz */ qry->targetList = NIL; foreach(tl, selectQuery->targetList) { TargetEntry *tle = (TargetEntry *) lfirst(tl); Resdom *resnode = tle->resdom; Node *expr; if (resnode->resjunk) continue; if (tle->expr && IsA(tle->expr, Const)) expr = tle->expr; else expr = (Node *) makeVar(rtr->rtindex, resnode->resno, resnode->restype, resnode->restypmod, 0); resnode = copyObject(resnode); resnode->resno = (AttrNumber) pstate->p_last_resno++; qry->targetList = lappend(qry->targetList, makeTargetEntry(resnode, expr)); } } else { /* * For INSERT ... VALUES, transform the given list of values to * form a targetlist for the INSERT. */ qry->targetList = transformTargetList(pstate, stmt->targetList); } /* * Now we are done with SELECT-like processing, and can get on with * transforming the target list to match the INSERT target columns. */ /* Prepare to assign non-conflicting resnos to resjunk attributes */ if (pstate->p_last_resno <= pstate->p_target_relation->rd_rel->relnatts) pstate->p_last_resno = pstate->p_target_relation->rd_rel->relnatts + 1; /* Validate stmt->cols list, or build default list if no list given */ icolumns = checkInsertTargets(pstate, stmt->cols, &attrnos); /* * Prepare columns for assignment to target table. */ attnos = attrnos; foreach(tl, qry->targetList) { TargetEntry *tle = (TargetEntry *) lfirst(tl); ResTarget *col; if (icolumns == NIL || attnos == NIL) elog(ERROR, "INSERT has more expressions than target columns"); col = (ResTarget *) lfirst(icolumns); /* * When the value is to be set to the column default we can simply * drop it now and handle it later on using methods for missing * columns. */ if (!IsA(tle, InsertDefault)) { Assert(IsA(col, ResTarget)); Assert(!tle->resdom->resjunk); updateTargetListEntry(pstate, tle, col->name, lfirsti(attnos), col->indirection); } else { icolumns = lremove(icolumns, icolumns); attnos = lremove(attnos, attnos); qry->targetList = lremove(tle, qry->targetList); } icolumns = lnext(icolumns); attnos = lnext(attnos); } /* * Ensure that the targetlist has the same number of entries * that were present in the columns list. Don't do the check * for select statements. */ if (stmt->cols != NIL && (icolumns != NIL || attnos != NIL)) elog(ERROR, "INSERT has more target columns than expressions"); /* done building the range table and jointree */ qry->rtable = pstate->p_rtable; qry->jointree = makeFromExpr(pstate->p_joinlist, NULL); qry->hasSubLinks = pstate->p_hasSubLinks; qry->hasAggs = pstate->p_hasAggs; if (pstate->p_hasAggs) parseCheckAggregates(pstate, qry, NULL); return qry; } /* * makeObjectName() * * Create a name for an implicitly created index, sequence, constraint, etc. * * The parameters are: the original table name, the original field name, and * a "type" string (such as "seq" or "pkey"). The field name and/or type * can be NULL if not relevant. * * The result is a palloc'd string. * * The basic result we want is "name1_name2_type", omitting "_name2" or * "_type" when those parameters are NULL. However, we must generate * a name with less than NAMEDATALEN characters! So, we truncate one or * both names if necessary to make a short-enough string. The type part * is never truncated (so it had better be reasonably short). * * To reduce the probability of collisions, we might someday add more * smarts to this routine, like including some "hash" characters computed * from the truncated characters. Currently it seems best to keep it simple, * so that the generated names are easily predictable by a person. */ char * makeObjectName(char *name1, char *name2, char *typename) { char *name; int overhead = 0; /* chars needed for type and underscores */ int availchars; /* chars available for name(s) */ int name1chars; /* chars allocated to name1 */ int name2chars; /* chars allocated to name2 */ int ndx; name1chars = strlen(name1); if (name2) { name2chars = strlen(name2); overhead++; /* allow for separating underscore */ } else name2chars = 0; if (typename) overhead += strlen(typename) + 1; availchars = NAMEDATALEN - 1 - overhead; /* * If we must truncate, preferentially truncate the longer name. This * logic could be expressed without a loop, but it's simple and * obvious as a loop. */ while (name1chars + name2chars > availchars) { if (name1chars > name2chars) name1chars--; else name2chars--; } #ifdef MULTIBYTE if (name1) name1chars = pg_mbcliplen(name1, name1chars, name1chars); if (name2) name2chars = pg_mbcliplen(name2, name2chars, name2chars); #endif /* Now construct the string using the chosen lengths */ name = palloc(name1chars + name2chars + overhead + 1); strncpy(name, name1, name1chars); ndx = name1chars; if (name2) { name[ndx++] = '_'; strncpy(name + ndx, name2, name2chars); ndx += name2chars; } if (typename) { name[ndx++] = '_'; strcpy(name + ndx, typename); } else name[ndx] = '\0'; return name; } static char * CreateIndexName(char *table_name, char *column_name, char *label, List *indices) { int pass = 0; char *iname = NULL; List *ilist; char typename[NAMEDATALEN]; /* * The type name for makeObjectName is label, or labelN if that's * necessary to prevent collisions among multiple indexes for the same * table. Note there is no check for collisions with already-existing * indexes, only among the indexes we're about to create now; this * ought to be improved someday. */ strcpy(typename, label); for (;;) { iname = makeObjectName(table_name, column_name, typename); foreach(ilist, indices) { IndexStmt *index = lfirst(ilist); if (index->idxname != NULL && strcmp(iname, index->idxname) == 0) break; } /* ran through entire list? then no name conflict found so done */ if (ilist == NIL) break; /* found a conflict, so try a new name component */ pfree(iname); sprintf(typename, "%s%d", label, ++pass); } return iname; } /* * transformCreateStmt - * transforms the "create table" statement * SQL92 allows constraints to be scattered all over, so thumb through * the columns and collect all constraints into one place. * If there are any implied indices (e.g. UNIQUE or PRIMARY KEY) * then expand those into multiple IndexStmt blocks. * - thomas 1997-12-02 */ static Query * transformCreateStmt(ParseState *pstate, CreateStmt *stmt, List **extras_before, List **extras_after) { CreateStmtContext cxt; Query *q; List *elements; cxt.stmtType = "CREATE TABLE"; cxt.relation = stmt->relation; cxt.inhRelations = stmt->inhRelations; cxt.hasoids = stmt->hasoids; cxt.relOid = InvalidOid; cxt.columns = NIL; cxt.ckconstraints = NIL; cxt.fkconstraints = NIL; cxt.ixconstraints = NIL; cxt.blist = NIL; cxt.alist = NIL; cxt.pkey = NULL; /* * Run through each primary element in the table creation clause. * Separate column defs from constraints, and do preliminary analysis. */ foreach(elements, stmt->tableElts) { Node *element = lfirst(elements); switch (nodeTag(element)) { case T_ColumnDef: transformColumnDefinition(pstate, &cxt, (ColumnDef *) element); break; case T_Constraint: transformTableConstraint(pstate, &cxt, (Constraint *) element); break; case T_FkConstraint: /* No pre-transformation needed */ cxt.fkconstraints = lappend(cxt.fkconstraints, element); break; default: elog(ERROR, "parser: unrecognized node (internal error)"); } } Assert(stmt->constraints == NIL); /* * Postprocess constraints that give rise to index definitions. */ transformIndexConstraints(pstate, &cxt); /* * Postprocess foreign-key constraints. */ transformFKConstraints(pstate, &cxt); /* * Output results. */ q = makeNode(Query); q->commandType = CMD_UTILITY; q->utilityStmt = (Node *) stmt; stmt->tableElts = cxt.columns; stmt->constraints = cxt.ckconstraints; *extras_before = nconc (*extras_before, cxt.blist); *extras_after = nconc (cxt.alist, *extras_after); return q; } static void transformColumnDefinition(ParseState *pstate, CreateStmtContext *cxt, ColumnDef *column) { bool is_serial; bool saw_nullable; Constraint *constraint; List *clist; Ident *key; cxt->columns = lappend(cxt->columns, column); /* Check for SERIAL pseudo-types */ is_serial = false; if (length(column->typename->names) == 1) { char *typname = strVal(lfirst(column->typename->names)); if (strcmp(typname, "serial") == 0 || strcmp(typname, "serial4") == 0) { is_serial = true; column->typename->names = NIL; column->typename->typeid = INT4OID; } else if (strcmp(typname, "bigserial") == 0 || strcmp(typname, "serial8") == 0) { is_serial = true; column->typename->names = NIL; column->typename->typeid = INT8OID; } } /* Do necessary work on the column type declaration */ transformColumnType(pstate, column); /* Special actions for SERIAL pseudo-types */ if (is_serial) { char *sname; char *snamespace; char *qstring; A_Const *snamenode; FuncCall *funccallnode; CreateSeqStmt *seqstmt; /* * Determine name and namespace to use for the sequence. */ sname = makeObjectName(cxt->relation->relname, column->colname, "seq"); snamespace = get_namespace_name(RangeVarGetCreationNamespace(cxt->relation)); elog(NOTICE, "%s will create implicit sequence '%s' for SERIAL column '%s.%s'", cxt->stmtType, sname, cxt->relation->relname, column->colname); /* * Build a CREATE SEQUENCE command to create the sequence object, * and add it to the list of things to be done before this * CREATE/ALTER TABLE. */ seqstmt = makeNode(CreateSeqStmt); seqstmt->sequence = makeRangeVar(snamespace, sname); seqstmt->options = NIL; cxt->blist = lappend(cxt->blist, seqstmt); /* * Mark the ColumnDef so that during execution, an appropriate * dependency will be added from the sequence to the column. */ column->support = makeRangeVar(snamespace, sname); /* * Create appropriate constraints for SERIAL. We do this in full, * rather than shortcutting, so that we will detect any * conflicting constraints the user wrote (like a different * DEFAULT). * * Create an expression tree representing the function call * nextval('"sequencename"') */ qstring = quote_qualified_identifier(snamespace, sname); snamenode = makeNode(A_Const); snamenode->val.type = T_String; snamenode->val.val.str = qstring; funccallnode = makeNode(FuncCall); funccallnode->funcname = SystemFuncName("nextval"); funccallnode->args = makeList1(snamenode); funccallnode->agg_star = false; funccallnode->agg_distinct = false; constraint = makeNode(Constraint); constraint->contype = CONSTR_DEFAULT; constraint->name = sname; constraint->raw_expr = (Node *) funccallnode; constraint->cooked_expr = NULL; constraint->keys = NIL; column->constraints = lappend(column->constraints, constraint); constraint = makeNode(Constraint); constraint->contype = CONSTR_UNIQUE; constraint->name = NULL; /* assign later */ column->constraints = lappend(column->constraints, constraint); constraint = makeNode(Constraint); constraint->contype = CONSTR_NOTNULL; column->constraints = lappend(column->constraints, constraint); } /* Process column constraints, if any... */ transformConstraintAttrs(column->constraints); saw_nullable = false; foreach(clist, column->constraints) { constraint = lfirst(clist); /* * If this column constraint is a FOREIGN KEY constraint, then we * fill in the current attributes name and throw it into the list * of FK constraints to be processed later. */ if (IsA(constraint, FkConstraint)) { FkConstraint *fkconstraint = (FkConstraint *) constraint; Ident *id = makeNode(Ident); id->name = column->colname; fkconstraint->fk_attrs = makeList1(id); cxt->fkconstraints = lappend(cxt->fkconstraints, fkconstraint); continue; } Assert(IsA(constraint, Constraint)); switch (constraint->contype) { case CONSTR_NULL: if (saw_nullable && column->is_not_null) elog(ERROR, "%s/(NOT) NULL conflicting declaration for '%s.%s'", cxt->stmtType, (cxt->relation)->relname, column->colname); column->is_not_null = FALSE; saw_nullable = true; break; case CONSTR_NOTNULL: if (saw_nullable && !column->is_not_null) elog(ERROR, "%s/(NOT) NULL conflicting declaration for '%s.%s'", cxt->stmtType, (cxt->relation)->relname, column->colname); column->is_not_null = TRUE; saw_nullable = true; break; case CONSTR_DEFAULT: if (column->raw_default != NULL) elog(ERROR, "%s/DEFAULT multiple values specified for '%s.%s'", cxt->stmtType, (cxt->relation)->relname, column->colname); column->raw_default = constraint->raw_expr; Assert(constraint->cooked_expr == NULL); break; case CONSTR_PRIMARY: if (constraint->name == NULL) constraint->name = makeObjectName((cxt->relation)->relname, NULL, "pkey"); if (constraint->keys == NIL) { key = makeNode(Ident); key->name = pstrdup(column->colname); constraint->keys = makeList1(key); } cxt->ixconstraints = lappend(cxt->ixconstraints, constraint); break; case CONSTR_UNIQUE: if (constraint->name == NULL) constraint->name = makeObjectName((cxt->relation)->relname, column->colname, "key"); if (constraint->keys == NIL) { key = makeNode(Ident); key->name = pstrdup(column->colname); constraint->keys = makeList1(key); } cxt->ixconstraints = lappend(cxt->ixconstraints, constraint); break; case CONSTR_CHECK: if (constraint->name == NULL) constraint->name = makeObjectName((cxt->relation)->relname, column->colname, NULL); cxt->ckconstraints = lappend(cxt->ckconstraints, constraint); break; case CONSTR_ATTR_DEFERRABLE: case CONSTR_ATTR_NOT_DEFERRABLE: case CONSTR_ATTR_DEFERRED: case CONSTR_ATTR_IMMEDIATE: /* transformConstraintAttrs took care of these */ break; default: elog(ERROR, "parser: unrecognized constraint (internal error)"); break; } } } static void transformTableConstraint(ParseState *pstate, CreateStmtContext *cxt, Constraint *constraint) { switch (constraint->contype) { case CONSTR_PRIMARY: if (constraint->name == NULL) constraint->name = makeObjectName((cxt->relation)->relname, NULL, "pkey"); cxt->ixconstraints = lappend(cxt->ixconstraints, constraint); break; case CONSTR_UNIQUE: cxt->ixconstraints = lappend(cxt->ixconstraints, constraint); break; case CONSTR_CHECK: cxt->ckconstraints = lappend(cxt->ckconstraints, constraint); break; case CONSTR_NULL: case CONSTR_NOTNULL: case CONSTR_DEFAULT: case CONSTR_ATTR_DEFERRABLE: case CONSTR_ATTR_NOT_DEFERRABLE: case CONSTR_ATTR_DEFERRED: case CONSTR_ATTR_IMMEDIATE: elog(ERROR, "parser: illegal context for constraint (internal error)"); break; default: elog(ERROR, "parser: unrecognized constraint (internal error)"); break; } } static void transformIndexConstraints(ParseState *pstate, CreateStmtContext *cxt) { List *listptr; List *keys; IndexStmt *index; IndexElem *iparam; ColumnDef *column; List *columns; List *indexlist = NIL; /* * Run through the constraints that need to generate an index. For * PRIMARY KEY, mark each column as NOT NULL and create an index. For * UNIQUE, create an index as for PRIMARY KEY, but do not insist on * NOT NULL. */ foreach(listptr, cxt->ixconstraints) { Constraint *constraint = lfirst(listptr); Assert(IsA(constraint, Constraint)); Assert((constraint->contype == CONSTR_PRIMARY) || (constraint->contype == CONSTR_UNIQUE)); index = makeNode(IndexStmt); index->unique = true; index->primary = (constraint->contype == CONSTR_PRIMARY); if (index->primary) { /* In ALTER TABLE case, a primary index might already exist */ if (cxt->pkey != NULL || (OidIsValid(cxt->relOid) && relationHasPrimaryKey(cxt->relOid))) elog(ERROR, "%s / PRIMARY KEY multiple primary keys" " for table '%s' are not allowed", cxt->stmtType, (cxt->relation)->relname); cxt->pkey = index; } index->isconstraint = true; if (constraint->name != NULL) index->idxname = pstrdup(constraint->name); else if (constraint->contype == CONSTR_PRIMARY) index->idxname = makeObjectName((cxt->relation)->relname, NULL, "pkey"); else index->idxname = NULL; /* will set it later */ index->relation = cxt->relation; index->accessMethod = DEFAULT_INDEX_TYPE; index->indexParams = NIL; index->whereClause = NULL; /* * Make sure referenced keys exist. If we are making a PRIMARY * KEY index, also make sure they are NOT NULL. */ foreach(keys, constraint->keys) { Ident *key = (Ident *) lfirst(keys); bool found = false; Assert(IsA(key, Ident)); column = NULL; foreach(columns, cxt->columns) { column = lfirst(columns); Assert(IsA(column, ColumnDef)); if (strcmp(column->colname, key->name) == 0) { found = true; break; } } if (found) { /* found column in the new table; force it to be NOT NULL */ if (constraint->contype == CONSTR_PRIMARY) column->is_not_null = TRUE; } else if (SystemAttributeByName(key->name, cxt->hasoids) != NULL) { /* * column will be a system column in the new table, so * accept it. System columns can't ever be null, so no * need to worry about PRIMARY/NOT NULL constraint. */ found = true; } else if (cxt->inhRelations) { /* try inherited tables */ List *inher; foreach(inher, cxt->inhRelations) { RangeVar *inh = lfirst(inher); Relation rel; int count; Assert(IsA(inh, RangeVar)); rel = heap_openrv(inh, AccessShareLock); if (rel->rd_rel->relkind != RELKIND_RELATION) elog(ERROR, "inherited table \"%s\" is not a relation", inh->relname); for (count = 0; count < rel->rd_att->natts; count++) { Form_pg_attribute inhattr = rel->rd_att->attrs[count]; char *inhname = NameStr(inhattr->attname); if (inhattr->attisdropped) continue; if (strcmp(key->name, inhname) == 0) { found = true; /* * If the column is inherited, we currently * have no easy way to force it to be NOT * NULL. Only way I can see to fix this would * be to convert the inherited-column info to * ColumnDef nodes before we reach this point, * and then create the table from those nodes * rather than referencing the parent tables * later. That would likely be cleaner, but * too much work to contemplate right now. * Instead, raise an error if the inherited * column won't be NOT NULL. (Would a WARNING * be more reasonable?) */ if (constraint->contype == CONSTR_PRIMARY && !inhattr->attnotnull) elog(ERROR, "inherited attribute \"%s\" cannot be a PRIMARY KEY because it is not marked NOT NULL", inhname); break; } } heap_close(rel, NoLock); if (found) break; } } else if (OidIsValid(cxt->relOid)) { /* ALTER TABLE case: does column already exist? */ HeapTuple atttuple; atttuple = SearchSysCacheAttName(cxt->relOid, key->name); if (HeapTupleIsValid(atttuple)) { found = true; /* * We require pre-existing column to be already marked * NOT NULL. */ if (constraint->contype == CONSTR_PRIMARY && !((Form_pg_attribute) GETSTRUCT(atttuple))->attnotnull) elog(ERROR, "Existing attribute \"%s\" cannot be a PRIMARY KEY because it is not marked NOT NULL", key->name); ReleaseSysCache(atttuple); } } if (!found) elog(ERROR, "%s: column \"%s\" named in key does not exist", cxt->stmtType, key->name); /* Check for PRIMARY KEY(foo, foo) */ foreach(columns, index->indexParams) { iparam = (IndexElem *) lfirst(columns); if (iparam->name && strcmp(key->name, iparam->name) == 0) elog(ERROR, "%s: column \"%s\" appears twice in %s constraint", cxt->stmtType, key->name, index->primary ? "PRIMARY KEY" : "UNIQUE"); } /* OK, add it to the index definition */ iparam = makeNode(IndexElem); iparam->name = pstrdup(key->name); iparam->funcname = NIL; iparam->args = NIL; iparam->opclass = NIL; index->indexParams = lappend(index->indexParams, iparam); } indexlist = lappend(indexlist, index); } /* * Scan the index list and remove any redundant index specifications. * This can happen if, for instance, the user writes SERIAL PRIMARY * KEY or SERIAL UNIQUE. A strict reading of SQL92 would suggest * raising an error instead, but that strikes me as too * anal-retentive. - tgl 2001-02-14 * * XXX in ALTER TABLE case, it'd be nice to look for duplicate * pre-existing indexes, too. */ cxt->alist = NIL; if (cxt->pkey != NULL) { /* Make sure we keep the PKEY index in preference to others... */ cxt->alist = makeList1(cxt->pkey); } while (indexlist != NIL) { index = lfirst(indexlist); /* if it's pkey, it's already in cxt->alist */ if (index != cxt->pkey) { bool keep = true; List *priorlist; foreach(priorlist, cxt->alist) { IndexStmt *priorindex = lfirst(priorlist); if (equal(index->indexParams, priorindex->indexParams)) { /* * If the prior index is as yet unnamed, and this one * is named, then transfer the name to the prior * index. This ensures that if we have named and * unnamed constraints, we'll use (at least one of) * the names for the index. */ if (priorindex->idxname == NULL) priorindex->idxname = index->idxname; keep = false; break; } } if (keep) cxt->alist = lappend(cxt->alist, index); } indexlist = lnext(indexlist); } /* * Finally, select unique names for all not-previously-named indices, * and display WARNING messages. * * XXX in ALTER TABLE case, we fail to consider name collisions against * pre-existing indexes. */ foreach(indexlist, cxt->alist) { index = lfirst(indexlist); if (index->idxname == NULL && index->indexParams != NIL) { iparam = lfirst(index->indexParams); index->idxname = CreateIndexName(cxt->relation->relname, iparam->name ? iparam->name : strVal(llast(iparam->funcname)), "key", cxt->alist); } if (index->idxname == NULL) /* should not happen */ elog(ERROR, "%s: failed to make implicit index name", cxt->stmtType); elog(NOTICE, "%s / %s%s will create implicit index '%s' for table '%s'", cxt->stmtType, (strcmp(cxt->stmtType, "ALTER TABLE") == 0) ? "ADD " : "", (index->primary ? "PRIMARY KEY" : "UNIQUE"), index->idxname, cxt->relation->relname); } } static void transformFKConstraints(ParseState *pstate, CreateStmtContext *cxt) { List *fkactions = NIL; List *fkclist; if (cxt->fkconstraints == NIL) return; elog(NOTICE, "%s will create implicit trigger(s) for FOREIGN KEY check(s)", cxt->stmtType); foreach(fkclist, cxt->fkconstraints) { FkConstraint *fkconstraint = (FkConstraint *) lfirst(fkclist); Oid pktypoid[INDEX_MAX_KEYS]; Oid fktypoid[INDEX_MAX_KEYS]; int i; int attnum; List *fkattrs; for (attnum = 0; attnum < INDEX_MAX_KEYS; attnum++) pktypoid[attnum] = fktypoid[attnum] = InvalidOid; /* * Look up the referencing attributes to make sure they exist (or * will exist) in this table, and remember their type OIDs. */ attnum = 0; foreach(fkattrs, fkconstraint->fk_attrs) { Ident *fkattr = lfirst(fkattrs); if (attnum >= INDEX_MAX_KEYS) elog(ERROR, "Can only have %d keys in a foreign key", INDEX_MAX_KEYS); fktypoid[attnum++] = transformFkeyGetColType(cxt, fkattr->name); } /* * If the attribute list for the referenced table was omitted, * lookup the definition of the primary key. */ if (fkconstraint->pk_attrs == NIL) { if (strcmp(fkconstraint->pktable->relname, (cxt->relation)->relname) != 0) transformFkeyGetPrimaryKey(fkconstraint, pktypoid); else if (cxt->pkey != NULL) { /* Use the to-be-created primary key */ List *attr; attnum = 0; foreach(attr, cxt->pkey->indexParams) { IndexElem *ielem = lfirst(attr); Ident *pkattr = (Ident *) makeNode(Ident); Assert(ielem->name); /* no func index here */ pkattr->name = pstrdup(ielem->name); fkconstraint->pk_attrs = lappend(fkconstraint->pk_attrs, pkattr); if (attnum >= INDEX_MAX_KEYS) elog(ERROR, "Can only have %d keys in a foreign key", INDEX_MAX_KEYS); pktypoid[attnum++] = transformFkeyGetColType(cxt, ielem->name); } } else { /* In ALTER TABLE case, primary key may already exist */ if (OidIsValid(cxt->relOid)) transformFkeyGetPrimaryKey(fkconstraint, pktypoid); else elog(ERROR, "PRIMARY KEY for referenced table \"%s\" not found", fkconstraint->pktable->relname); } } else { /* Validate the specified referenced key list */ if (strcmp(fkconstraint->pktable->relname, (cxt->relation)->relname) != 0) transformFkeyCheckAttrs(fkconstraint, pktypoid); else { /* Look for a matching new unique/primary constraint */ List *index; bool found = false; foreach(index, cxt->alist) { IndexStmt *ind = lfirst(index); List *pkattrs; if (!ind->unique) continue; if (length(ind->indexParams) != length(fkconstraint->pk_attrs)) continue; attnum = 0; foreach(pkattrs, fkconstraint->pk_attrs) { Ident *pkattr = lfirst(pkattrs); List *indparms; found = false; foreach(indparms, ind->indexParams) { IndexElem *indparm = lfirst(indparms); if (indparm->name && strcmp(indparm->name, pkattr->name) == 0) { found = true; break; } } if (!found) break; if (attnum >= INDEX_MAX_KEYS) elog(ERROR, "Can only have %d keys in a foreign key", INDEX_MAX_KEYS); pktypoid[attnum++] = transformFkeyGetColType(cxt, pkattr->name); } if (found) break; } if (!found) { /* * In ALTER TABLE case, such an index may already * exist */ if (OidIsValid(cxt->relOid)) transformFkeyCheckAttrs(fkconstraint, pktypoid); else elog(ERROR, "UNIQUE constraint matching given keys for referenced table \"%s\" not found", fkconstraint->pktable->relname); } } } /* Be sure referencing and referenced column types are comparable */ for (i = 0; i < INDEX_MAX_KEYS && fktypoid[i] != 0; i++) { /* * fktypoid[i] is the foreign key table's i'th element's type * pktypoid[i] is the primary key table's i'th element's type * * We let oper() do our work for us, including elog(ERROR) if * the types don't compare with = */ Operator o = oper(makeList1(makeString("=")), fktypoid[i], pktypoid[i], false); ReleaseSysCache(o); } /* * For ALTER TABLE ADD CONSTRAINT, we're done. For CREATE TABLE, * gin up an ALTER TABLE ADD CONSTRAINT command to execute after * the basic CREATE TABLE is complete. */ if (strcmp(cxt->stmtType, "CREATE TABLE") == 0) { AlterTableStmt *alterstmt = makeNode(AlterTableStmt); alterstmt->subtype = 'c'; /* preprocessed add constraint */ alterstmt->relation = cxt->relation; alterstmt->name = NULL; alterstmt->def = (Node *) makeList1(fkconstraint); /* Don't need to scan the table contents in this case */ fkconstraint->skip_validation = true; fkactions = lappend(fkactions, (Node *) alterstmt); } } /* * Attach completed list of extra actions to cxt->alist. We cannot do * this earlier, because we assume above that cxt->alist still holds * only IndexStmts. */ cxt->alist = nconc(cxt->alist, fkactions); } /* * transformIndexStmt - * transforms the qualification of the index statement */ static Query * transformIndexStmt(ParseState *pstate, IndexStmt *stmt) { Query *qry; RangeTblEntry *rte; qry = makeNode(Query); qry->commandType = CMD_UTILITY; /* take care of the where clause */ if (stmt->whereClause) { /* * Put the parent table into the rtable so that the WHERE clause * can refer to its fields without qualification. Note that this * only works if the parent table already exists --- so we can't * easily support predicates on indexes created implicitly by * CREATE TABLE. Fortunately, that's not necessary. */ rte = addRangeTableEntry(pstate, stmt->relation, NULL, false, true); /* no to join list, yes to namespace */ addRTEtoQuery(pstate, rte, false, true); stmt->whereClause = transformWhereClause(pstate, stmt->whereClause); } qry->hasSubLinks = pstate->p_hasSubLinks; stmt->rangetable = pstate->p_rtable; qry->utilityStmt = (Node *) stmt; return qry; } /* * transformRuleStmt - * transform a Create Rule Statement. The actions is a list of parse * trees which is transformed into a list of query trees. */ static Query * transformRuleStmt(ParseState *pstate, RuleStmt *stmt, List **extras_before, List **extras_after) { Query *qry; RangeTblEntry *oldrte; RangeTblEntry *newrte; qry = makeNode(Query); qry->commandType = CMD_UTILITY; qry->utilityStmt = (Node *) stmt; /* * To avoid deadlock, make sure the first thing we do is grab * AccessExclusiveLock on the target relation. This will be needed by * DefineQueryRewrite(), and we don't want to grab a lesser lock * beforehand. We don't need to hold a refcount on the relcache * entry, however. */ heap_close(heap_openrv(stmt->relation, AccessExclusiveLock), NoLock); /* * NOTE: 'OLD' must always have a varno equal to 1 and 'NEW' equal to * 2. Set up their RTEs in the main pstate for use in parsing the * rule qualification. */ Assert(pstate->p_rtable == NIL); oldrte = addRangeTableEntry(pstate, stmt->relation, makeAlias("*OLD*", NIL), false, true); newrte = addRangeTableEntry(pstate, stmt->relation, makeAlias("*NEW*", NIL), false, true); /* Must override addRangeTableEntry's default access-check flags */ oldrte->checkForRead = false; newrte->checkForRead = false; /* * They must be in the namespace too for lookup purposes, but only add * the one(s) that are relevant for the current kind of rule. In an * UPDATE rule, quals must refer to OLD.field or NEW.field to be * unambiguous, but there's no need to be so picky for INSERT & * DELETE. (Note we marked the RTEs "inFromCl = true" above to allow * unqualified references to their fields.) We do not add them to the * joinlist. */ switch (stmt->event) { case CMD_SELECT: addRTEtoQuery(pstate, oldrte, false, true); break; case CMD_UPDATE: addRTEtoQuery(pstate, oldrte, false, true); addRTEtoQuery(pstate, newrte, false, true); break; case CMD_INSERT: addRTEtoQuery(pstate, newrte, false, true); break; case CMD_DELETE: addRTEtoQuery(pstate, oldrte, false, true); break; default: elog(ERROR, "transformRuleStmt: unexpected event type %d", (int) stmt->event); break; } /* take care of the where clause */ stmt->whereClause = transformWhereClause(pstate, stmt->whereClause); if (length(pstate->p_rtable) != 2) /* naughty, naughty... */ elog(ERROR, "Rule WHERE condition may not contain references to other relations"); /* save info about sublinks in where clause */ qry->hasSubLinks = pstate->p_hasSubLinks; /* * 'instead nothing' rules with a qualification need a query * rangetable so the rewrite handler can add the negated rule * qualification to the original query. We create a query with the new * command type CMD_NOTHING here that is treated specially by the * rewrite system. */ if (stmt->actions == NIL) { Query *nothing_qry = makeNode(Query); nothing_qry->commandType = CMD_NOTHING; nothing_qry->rtable = pstate->p_rtable; nothing_qry->jointree = makeFromExpr(NIL, NULL); /* no join wanted */ stmt->actions = makeList1(nothing_qry); } else { List *oldactions; List *newactions = NIL; /* * transform each statement, like parse_analyze() */ foreach(oldactions, stmt->actions) { Node *action = (Node *) lfirst(oldactions); ParseState *sub_pstate = make_parsestate(pstate->parentParseState); Query *sub_qry, *top_subqry; bool has_old, has_new; /* * Set up OLD/NEW in the rtable for this statement. The * entries are marked not inFromCl because we don't want them * to be referred to by unqualified field names nor "*" in the * rule actions. We must add them to the namespace, however, * or they won't be accessible at all. We decide later * whether to put them in the joinlist. */ oldrte = addRangeTableEntry(sub_pstate, stmt->relation, makeAlias("*OLD*", NIL), false, false); newrte = addRangeTableEntry(sub_pstate, stmt->relation, makeAlias("*NEW*", NIL), false, false); oldrte->checkForRead = false; newrte->checkForRead = false; addRTEtoQuery(sub_pstate, oldrte, false, true); addRTEtoQuery(sub_pstate, newrte, false, true); /* Transform the rule action statement */ top_subqry = transformStmt(sub_pstate, action, extras_before, extras_after); /* * We cannot support utility-statement actions (eg NOTIFY) * with nonempty rule WHERE conditions, because there's no way * to make the utility action execute conditionally. */ if (top_subqry->commandType == CMD_UTILITY && stmt->whereClause != NULL) elog(ERROR, "Rules with WHERE conditions may only have SELECT, INSERT, UPDATE, or DELETE actions"); /* * If the action is INSERT...SELECT, OLD/NEW have been pushed * down into the SELECT, and that's what we need to look at. * (Ugly kluge ... try to fix this when we redesign * querytrees.) */ sub_qry = getInsertSelectQuery(top_subqry, NULL); /* * Validate action's use of OLD/NEW, qual too */ has_old = rangeTableEntry_used((Node *) sub_qry, PRS2_OLD_VARNO, 0) || rangeTableEntry_used(stmt->whereClause, PRS2_OLD_VARNO, 0); has_new = rangeTableEntry_used((Node *) sub_qry, PRS2_NEW_VARNO, 0) || rangeTableEntry_used(stmt->whereClause, PRS2_NEW_VARNO, 0); switch (stmt->event) { case CMD_SELECT: if (has_old) elog(ERROR, "ON SELECT rule may not use OLD"); if (has_new) elog(ERROR, "ON SELECT rule may not use NEW"); break; case CMD_UPDATE: /* both are OK */ break; case CMD_INSERT: if (has_old) elog(ERROR, "ON INSERT rule may not use OLD"); break; case CMD_DELETE: if (has_new) elog(ERROR, "ON DELETE rule may not use NEW"); break; default: elog(ERROR, "transformRuleStmt: unexpected event type %d", (int) stmt->event); break; } /* * For efficiency's sake, add OLD to the rule action's * jointree only if it was actually referenced in the * statement or qual. * * For INSERT, NEW is not really a relation (only a reference to * the to-be-inserted tuple) and should never be added to the * jointree. * * For UPDATE, we treat NEW as being another kind of reference to * OLD, because it represents references to *transformed* * tuples of the existing relation. It would be wrong to * enter NEW separately in the jointree, since that would * cause a double join of the updated relation. It's also * wrong to fail to make a jointree entry if only NEW and not * OLD is mentioned. */ if (has_old || (has_new && stmt->event == CMD_UPDATE)) { /* hack so we can use addRTEtoQuery() */ sub_pstate->p_rtable = sub_qry->rtable; sub_pstate->p_joinlist = sub_qry->jointree->fromlist; addRTEtoQuery(sub_pstate, oldrte, true, false); sub_qry->jointree->fromlist = sub_pstate->p_joinlist; } newactions = lappend(newactions, top_subqry); release_pstate_resources(sub_pstate); pfree(sub_pstate); } stmt->actions = newactions; } return qry; } /* * transformSelectStmt - * transforms a Select Statement * * Note: this is also used for DECLARE CURSOR statements. */ static Query * transformSelectStmt(ParseState *pstate, SelectStmt *stmt) { Query *qry = makeNode(Query); Node *qual; qry->commandType = CMD_SELECT; if (stmt->portalname) { /* DECLARE CURSOR */ if (stmt->into) elog(ERROR, "DECLARE CURSOR must not specify INTO"); if (stmt->forUpdate) elog(ERROR, "DECLARE/UPDATE is not supported" "\n\tCursors must be READ ONLY"); /* * 15 august 1991 -- since 3.0 postgres does locking right, we * discovered that portals were violating locking protocol. portal * locks cannot span xacts. as a short-term fix, we installed the * check here. -- mao */ if (!IsTransactionBlock()) elog(ERROR, "DECLARE CURSOR may only be used in begin/end transaction blocks"); qry->into = makeNode(RangeVar); qry->into->relname = stmt->portalname; qry->isPortal = TRUE; qry->isBinary = stmt->binary; /* internal portal */ } else { /* SELECT */ qry->into = stmt->into; qry->isPortal = FALSE; qry->isBinary = FALSE; } /* make FOR UPDATE clause available to addRangeTableEntry */ pstate->p_forUpdate = stmt->forUpdate; /* process the FROM clause */ transformFromClause(pstate, stmt->fromClause); /* transform targetlist */ qry->targetList = transformTargetList(pstate, stmt->targetList); if (stmt->intoColNames) applyColumnNames(qry->targetList, stmt->intoColNames); /* transform WHERE */ qual = transformWhereClause(pstate, stmt->whereClause); /* * Initial processing of HAVING clause is just like WHERE clause. * Additional work will be done in optimizer/plan/planner.c. */ qry->havingQual = transformWhereClause(pstate, stmt->havingClause); qry->groupClause = transformGroupClause(pstate, stmt->groupClause, qry->targetList); qry->sortClause = transformSortClause(pstate, stmt->sortClause, qry->targetList); qry->distinctClause = transformDistinctClause(pstate, stmt->distinctClause, qry->targetList, &qry->sortClause); qry->limitOffset = stmt->limitOffset; qry->limitCount = stmt->limitCount; qry->hasSubLinks = pstate->p_hasSubLinks; qry->hasAggs = pstate->p_hasAggs; if (pstate->p_hasAggs || qry->groupClause || qry->havingQual) parseCheckAggregates(pstate, qry, qual); qry->rtable = pstate->p_rtable; qry->jointree = makeFromExpr(pstate->p_joinlist, qual); if (stmt->forUpdate != NIL) transformForUpdate(qry, stmt->forUpdate); return qry; } /* * transformSetOperationsStmt - * transforms a set-operations tree * * A set-operation tree is just a SELECT, but with UNION/INTERSECT/EXCEPT * structure to it. We must transform each leaf SELECT and build up a top- * level Query that contains the leaf SELECTs as subqueries in its rangetable. * The tree of set operations is converted into the setOperations field of * the top-level Query. */ static Query * transformSetOperationStmt(ParseState *pstate, SelectStmt *stmt) { Query *qry = makeNode(Query); SelectStmt *leftmostSelect; int leftmostRTI; Query *leftmostQuery; SetOperationStmt *sostmt; RangeVar *into; List *intoColNames; char *portalname; bool binary; List *sortClause; Node *limitOffset; Node *limitCount; List *forUpdate; Node *node; List *lefttl, *dtlist, *targetvars, *targetnames, *sv_namespace, *sv_rtable; RangeTblEntry *jrte; RangeTblRef *jrtr; int tllen; qry->commandType = CMD_SELECT; /* * Find leftmost leaf SelectStmt; extract the one-time-only items from * it and from the top-level node. */ leftmostSelect = stmt->larg; while (leftmostSelect && leftmostSelect->op != SETOP_NONE) leftmostSelect = leftmostSelect->larg; Assert(leftmostSelect && IsA(leftmostSelect, SelectStmt) && leftmostSelect->larg == NULL); into = leftmostSelect->into; intoColNames = leftmostSelect->intoColNames; portalname = stmt->portalname; binary = stmt->binary; /* clear them to prevent complaints in transformSetOperationTree() */ leftmostSelect->into = NULL; leftmostSelect->intoColNames = NIL; stmt->portalname = NULL; stmt->binary = false; /* * These are not one-time, exactly, but we want to process them here * and not let transformSetOperationTree() see them --- else it'll * just recurse right back here! */ sortClause = stmt->sortClause; limitOffset = stmt->limitOffset; limitCount = stmt->limitCount; forUpdate = stmt->forUpdate; stmt->sortClause = NIL; stmt->limitOffset = NULL; stmt->limitCount = NULL; stmt->forUpdate = NIL; /* We don't support forUpdate with set ops at the moment. */ if (forUpdate) elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT"); /* * Recursively transform the components of the tree. */ sostmt = (SetOperationStmt *) transformSetOperationTree(pstate, stmt); Assert(sostmt && IsA(sostmt, SetOperationStmt)); qry->setOperations = (Node *) sostmt; /* * Re-find leftmost SELECT (now it's a sub-query in rangetable) */ node = sostmt->larg; while (node && IsA(node, SetOperationStmt)) node = ((SetOperationStmt *) node)->larg; Assert(node && IsA(node, RangeTblRef)); leftmostRTI = ((RangeTblRef *) node)->rtindex; leftmostQuery = rt_fetch(leftmostRTI, pstate->p_rtable)->subquery; Assert(leftmostQuery != NULL); /* * Generate dummy targetlist for outer query using column names of * leftmost select and common datatypes of topmost set operation. Also * make lists of the dummy vars and their names for use in parsing * ORDER BY. */ qry->targetList = NIL; targetvars = NIL; targetnames = NIL; lefttl = leftmostQuery->targetList; foreach(dtlist, sostmt->colTypes) { Oid colType = (Oid) lfirsti(dtlist); Resdom *leftResdom = ((TargetEntry *) lfirst(lefttl))->resdom; char *colName = pstrdup(leftResdom->resname); Resdom *resdom; Node *expr; resdom = makeResdom((AttrNumber) pstate->p_last_resno++, colType, -1, colName, false); expr = (Node *) makeVar(1, leftResdom->resno, colType, -1, 0); qry->targetList = lappend(qry->targetList, makeTargetEntry(resdom, expr)); targetvars = lappend(targetvars, expr); targetnames = lappend(targetnames, makeString(colName)); lefttl = lnext(lefttl); } /* * Insert one-time items into top-level query * * This needs to agree with transformSelectStmt! */ if (portalname) { /* DECLARE CURSOR */ if (into) elog(ERROR, "DECLARE CURSOR must not specify INTO"); if (forUpdate) elog(ERROR, "DECLARE/UPDATE is not supported" "\n\tCursors must be READ ONLY"); /* * 15 august 1991 -- since 3.0 postgres does locking right, we * discovered that portals were violating locking protocol. portal * locks cannot span xacts. as a short-term fix, we installed the * check here. -- mao */ if (!IsTransactionBlock()) elog(ERROR, "DECLARE CURSOR may only be used in begin/end transaction blocks"); qry->into = makeNode(RangeVar); qry->into->relname = portalname; qry->isPortal = TRUE; qry->isBinary = binary; /* internal portal */ } else { /* SELECT */ qry->into = into; qry->isPortal = FALSE; qry->isBinary = FALSE; } /* * Any column names from CREATE TABLE AS need to be attached to both the * top level and the leftmost subquery. We do not do this earlier * because we do *not* want the targetnames list to be affected. */ if (intoColNames) { applyColumnNames(qry->targetList, intoColNames); applyColumnNames(leftmostQuery->targetList, intoColNames); } /* * As a first step towards supporting sort clauses that are * expressions using the output columns, generate a namespace entry * that makes the output columns visible. A Join RTE node is handy * for this, since we can easily control the Vars generated upon * matches. * * Note: we don't yet do anything useful with such cases, but at least * "ORDER BY upper(foo)" will draw the right error message rather than * "foo not found". */ jrte = addRangeTableEntryForJoin(NULL, targetnames, JOIN_INNER, targetvars, NULL, true); jrtr = makeNode(RangeTblRef); jrtr->rtindex = 1; sv_rtable = pstate->p_rtable; pstate->p_rtable = makeList1(jrte); sv_namespace = pstate->p_namespace; pstate->p_namespace = makeList1(jrtr); /* * For now, we don't support resjunk sort clauses on the output of a * setOperation tree --- you can only use the SQL92-spec options of * selecting an output column by name or number. Enforce by checking * that transformSortClause doesn't add any items to tlist. */ tllen = length(qry->targetList); qry->sortClause = transformSortClause(pstate, sortClause, qry->targetList); pstate->p_namespace = sv_namespace; pstate->p_rtable = sv_rtable; if (tllen != length(qry->targetList)) elog(ERROR, "ORDER BY on a UNION/INTERSECT/EXCEPT result must be on one of the result columns"); qry->limitOffset = limitOffset; qry->limitCount = limitCount; qry->hasSubLinks = pstate->p_hasSubLinks; qry->hasAggs = pstate->p_hasAggs; if (pstate->p_hasAggs || qry->groupClause || qry->havingQual) parseCheckAggregates(pstate, qry, NULL); qry->rtable = pstate->p_rtable; qry->jointree = makeFromExpr(pstate->p_joinlist, NULL); if (forUpdate != NIL) transformForUpdate(qry, forUpdate); return qry; } /* * transformSetOperationTree * Recursively transform leaves and internal nodes of a set-op tree */ static Node * transformSetOperationTree(ParseState *pstate, SelectStmt *stmt) { bool isLeaf; Assert(stmt && IsA(stmt, SelectStmt)); /* * Validity-check both leaf and internal SELECTs for disallowed ops. */ if (stmt->into) elog(ERROR, "INTO is only allowed on first SELECT of UNION/INTERSECT/EXCEPT"); if (stmt->portalname) /* should not happen */ elog(ERROR, "Portal may not appear in UNION/INTERSECT/EXCEPT"); /* We don't support forUpdate with set ops at the moment. */ if (stmt->forUpdate) elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT"); /* * If an internal node of a set-op tree has ORDER BY, UPDATE, or LIMIT * clauses attached, we need to treat it like a leaf node to generate * an independent sub-Query tree. Otherwise, it can be represented by * a SetOperationStmt node underneath the parent Query. */ if (stmt->op == SETOP_NONE) { Assert(stmt->larg == NULL && stmt->rarg == NULL); isLeaf = true; } else { Assert(stmt->larg != NULL && stmt->rarg != NULL); if (stmt->sortClause || stmt->limitOffset || stmt->limitCount || stmt->forUpdate) isLeaf = true; else isLeaf = false; } if (isLeaf) { /* Process leaf SELECT */ List *selectList; Query *selectQuery; char selectName[32]; RangeTblEntry *rte; RangeTblRef *rtr; /* * Transform SelectStmt into a Query. * * Note: previously transformed sub-queries don't affect the parsing * of this sub-query, because they are not in the toplevel * pstate's namespace list. */ selectList = parse_analyze((Node *) stmt, pstate); Assert(length(selectList) == 1); selectQuery = (Query *) lfirst(selectList); /* * Make the leaf query be a subquery in the top-level rangetable. */ sprintf(selectName, "*SELECT* %d", length(pstate->p_rtable) + 1); rte = addRangeTableEntryForSubquery(pstate, selectQuery, makeAlias(selectName, NIL), false); /* * Return a RangeTblRef to replace the SelectStmt in the set-op * tree. */ rtr = makeNode(RangeTblRef); /* assume new rte is at end */ rtr->rtindex = length(pstate->p_rtable); Assert(rte == rt_fetch(rtr->rtindex, pstate->p_rtable)); return (Node *) rtr; } else { /* Process an internal node (set operation node) */ SetOperationStmt *op = makeNode(SetOperationStmt); List *lcoltypes; List *rcoltypes; const char *context; context = (stmt->op == SETOP_UNION ? "UNION" : (stmt->op == SETOP_INTERSECT ? "INTERSECT" : "EXCEPT")); op->op = stmt->op; op->all = stmt->all; /* * Recursively transform the child nodes. */ op->larg = transformSetOperationTree(pstate, stmt->larg); op->rarg = transformSetOperationTree(pstate, stmt->rarg); /* * Verify that the two children have the same number of non-junk * columns, and determine the types of the merged output columns. */ lcoltypes = getSetColTypes(pstate, op->larg); rcoltypes = getSetColTypes(pstate, op->rarg); if (length(lcoltypes) != length(rcoltypes)) elog(ERROR, "Each %s query must have the same number of columns", context); op->colTypes = NIL; while (lcoltypes != NIL) { Oid lcoltype = (Oid) lfirsti(lcoltypes); Oid rcoltype = (Oid) lfirsti(rcoltypes); Oid rescoltype; rescoltype = select_common_type(makeListi2(lcoltype, rcoltype), context); op->colTypes = lappendi(op->colTypes, rescoltype); lcoltypes = lnext(lcoltypes); rcoltypes = lnext(rcoltypes); } return (Node *) op; } } /* * getSetColTypes * Get output column types of an (already transformed) set-op node */ static List * getSetColTypes(ParseState *pstate, Node *node) { if (IsA(node, RangeTblRef)) { RangeTblRef *rtr = (RangeTblRef *) node; RangeTblEntry *rte = rt_fetch(rtr->rtindex, pstate->p_rtable); Query *selectQuery = rte->subquery; List *result = NIL; List *tl; Assert(selectQuery != NULL); /* Get types of non-junk columns */ foreach(tl, selectQuery->targetList) { TargetEntry *tle = (TargetEntry *) lfirst(tl); Resdom *resnode = tle->resdom; if (resnode->resjunk) continue; result = lappendi(result, resnode->restype); } return result; } else if (IsA(node, SetOperationStmt)) { SetOperationStmt *op = (SetOperationStmt *) node; /* Result already computed during transformation of node */ Assert(op->colTypes != NIL); return op->colTypes; } else { elog(ERROR, "getSetColTypes: unexpected node %d", (int) nodeTag(node)); return NIL; /* keep compiler quiet */ } } /* Attach column names from a ColumnDef list to a TargetEntry list */ static void applyColumnNames(List *dst, List *src) { if (length(src) > length(dst)) elog(ERROR, "CREATE TABLE AS specifies too many column names"); while (src != NIL && dst != NIL) { TargetEntry *d = (TargetEntry *) lfirst(dst); ColumnDef *s = (ColumnDef *) lfirst(src); Assert(d->resdom && !d->resdom->resjunk); d->resdom->resname = pstrdup(s->colname); dst = lnext(dst); src = lnext(src); } } /* * transformUpdateStmt - * transforms an update statement */ static Query * transformUpdateStmt(ParseState *pstate, UpdateStmt *stmt) { Query *qry = makeNode(Query); Node *qual; List *origTargetList; List *tl; qry->commandType = CMD_UPDATE; pstate->p_is_update = true; qry->resultRelation = setTargetTable(pstate, stmt->relation, interpretInhOption(stmt->relation->inhOpt), true); /* * the FROM clause is non-standard SQL syntax. We used to be able to * do this with REPLACE in POSTQUEL so we keep the feature. */ transformFromClause(pstate, stmt->fromClause); qry->targetList = transformTargetList(pstate, stmt->targetList); qual = transformWhereClause(pstate, stmt->whereClause); qry->rtable = pstate->p_rtable; qry->jointree = makeFromExpr(pstate->p_joinlist, qual); qry->hasSubLinks = pstate->p_hasSubLinks; qry->hasAggs = pstate->p_hasAggs; if (pstate->p_hasAggs) parseCheckAggregates(pstate, qry, qual); /* * Now we are done with SELECT-like processing, and can get on with * transforming the target list to match the UPDATE target columns. */ /* Prepare to assign non-conflicting resnos to resjunk attributes */ if (pstate->p_last_resno <= pstate->p_target_relation->rd_rel->relnatts) pstate->p_last_resno = pstate->p_target_relation->rd_rel->relnatts + 1; /* Prepare non-junk columns for assignment to target table */ origTargetList = stmt->targetList; foreach(tl, qry->targetList) { TargetEntry *tle = (TargetEntry *) lfirst(tl); Resdom *resnode = tle->resdom; ResTarget *origTarget; if (resnode->resjunk) { /* * Resjunk nodes need no additional processing, but be sure * they have names and resnos that do not match any target * columns; else rewriter or planner might get confused. */ resnode->resname = "?resjunk?"; resnode->resno = (AttrNumber) pstate->p_last_resno++; continue; } if (origTargetList == NIL) elog(ERROR, "UPDATE target count mismatch --- internal error"); origTarget = (ResTarget *) lfirst(origTargetList); updateTargetListEntry(pstate, tle, origTarget->name, attnameAttNum(pstate->p_target_relation, origTarget->name, true), origTarget->indirection); origTargetList = lnext(origTargetList); } if (origTargetList != NIL) elog(ERROR, "UPDATE target count mismatch --- internal error"); return qry; } /* * tranformAlterTableStmt - * transform an Alter Table Statement */ static Query * transformAlterTableStmt(ParseState *pstate, AlterTableStmt *stmt, List **extras_before, List **extras_after) { CreateStmtContext cxt; Query *qry; /* * The only subtypes that currently require parse transformation * handling are 'A'dd column and Add 'C'onstraint. These largely * re-use code from CREATE TABLE. */ switch (stmt->subtype) { case 'A': cxt.stmtType = "ALTER TABLE"; cxt.relation = stmt->relation; cxt.inhRelations = NIL; cxt.relOid = RangeVarGetRelid(stmt->relation, false); cxt.hasoids = SearchSysCacheExists(ATTNUM, ObjectIdGetDatum(cxt.relOid), Int16GetDatum(ObjectIdAttributeNumber), 0, 0); cxt.columns = NIL; cxt.ckconstraints = NIL; cxt.fkconstraints = NIL; cxt.ixconstraints = NIL; cxt.blist = NIL; cxt.alist = NIL; cxt.pkey = NULL; Assert(IsA(stmt->def, ColumnDef)); transformColumnDefinition(pstate, &cxt, (ColumnDef *) stmt->def); transformIndexConstraints(pstate, &cxt); transformFKConstraints(pstate, &cxt); ((ColumnDef *) stmt->def)->constraints = cxt.ckconstraints; *extras_before = nconc(*extras_before, cxt.blist); *extras_after = nconc(cxt.alist, *extras_after); break; case 'C': cxt.stmtType = "ALTER TABLE"; cxt.relation = stmt->relation; cxt.inhRelations = NIL; cxt.relOid = RangeVarGetRelid(stmt->relation, false); cxt.hasoids = SearchSysCacheExists(ATTNUM, ObjectIdGetDatum(cxt.relOid), Int16GetDatum(ObjectIdAttributeNumber), 0, 0); cxt.columns = NIL; cxt.ckconstraints = NIL; cxt.fkconstraints = NIL; cxt.ixconstraints = NIL; cxt.blist = NIL; cxt.alist = NIL; cxt.pkey = NULL; if (IsA(stmt->def, Constraint)) transformTableConstraint(pstate, &cxt, (Constraint *) stmt->def); else if (IsA(stmt->def, FkConstraint)) cxt.fkconstraints = lappend(cxt.fkconstraints, stmt->def); else elog(ERROR, "Unexpected node type in ALTER TABLE ADD CONSTRAINT"); transformIndexConstraints(pstate, &cxt); transformFKConstraints(pstate, &cxt); Assert(cxt.columns == NIL); stmt->def = (Node *) nconc(cxt.ckconstraints, cxt.fkconstraints); *extras_before = nconc(*extras_before, cxt.blist); *extras_after = nconc(cxt.alist, *extras_after); break; case 'c': /* * Already-transformed ADD CONSTRAINT, so just make it look * like the standard case. */ stmt->subtype = 'C'; break; default: break; } qry = makeNode(Query); qry->commandType = CMD_UTILITY; qry->utilityStmt = (Node *) stmt; return qry; } /* exported so planner can check again after rewriting, query pullup, etc */ void CheckSelectForUpdate(Query *qry) { if (qry->setOperations) elog(ERROR, "SELECT FOR UPDATE is not allowed with UNION/INTERSECT/EXCEPT"); if (qry->distinctClause != NIL) elog(ERROR, "SELECT FOR UPDATE is not allowed with DISTINCT clause"); if (qry->groupClause != NIL) elog(ERROR, "SELECT FOR UPDATE is not allowed with GROUP BY clause"); if (qry->hasAggs) elog(ERROR, "SELECT FOR UPDATE is not allowed with AGGREGATE"); } static void transformForUpdate(Query *qry, List *forUpdate) { List *rowMarks = qry->rowMarks; List *l; List *rt; Index i; CheckSelectForUpdate(qry); if (lfirst(forUpdate) == NULL) { /* all tables used in query */ i = 0; foreach(rt, qry->rtable) { RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt); ++i; if (rte->rtekind == RTE_SUBQUERY) { /* FOR UPDATE of subquery is propagated to subquery's rels */ transformForUpdate(rte->subquery, makeList1(NULL)); } else { if (!intMember(i, rowMarks)) /* avoid duplicates */ rowMarks = lappendi(rowMarks, i); rte->checkForWrite = true; } } } else { /* just the named tables */ foreach(l, forUpdate) { char *relname = strVal(lfirst(l)); i = 0; foreach(rt, qry->rtable) { RangeTblEntry *rte = (RangeTblEntry *) lfirst(rt); ++i; if (strcmp(rte->eref->aliasname, relname) == 0) { if (rte->rtekind == RTE_SUBQUERY) { /* propagate to subquery */ transformForUpdate(rte->subquery, makeList1(NULL)); } else { if (!intMember(i, rowMarks)) /* avoid duplicates */ rowMarks = lappendi(rowMarks, i); rte->checkForWrite = true; } break; } } if (rt == NIL) elog(ERROR, "FOR UPDATE: relation \"%s\" not found in FROM clause", relname); } } qry->rowMarks = rowMarks; } /* * transformFkeyCheckAttrs - * * Make sure that the attributes of a referenced table * belong to a unique (or primary key) constraint. */ static void transformFkeyCheckAttrs(FkConstraint *fkconstraint, Oid *pktypoid) { Relation pkrel; List *indexoidlist, *indexoidscan; int i; bool found = false; /* * Open the referenced table */ pkrel = heap_openrv(fkconstraint->pktable, AccessShareLock); if (pkrel->rd_rel->relkind != RELKIND_RELATION) elog(ERROR, "Referenced relation \"%s\" is not a table", fkconstraint->pktable->relname); /* * Get the list of index OIDs for the table from the relcache, and * look up each one in the pg_index syscache for each unique one, and * then compare the attributes we were given to those defined. */ indexoidlist = RelationGetIndexList(pkrel); foreach(indexoidscan, indexoidlist) { Oid indexoid = lfirsti(indexoidscan); HeapTuple indexTuple; Form_pg_index indexStruct; found = false; indexTuple = SearchSysCache(INDEXRELID, ObjectIdGetDatum(indexoid), 0, 0, 0); if (!HeapTupleIsValid(indexTuple)) elog(ERROR, "transformFkeyCheckAttrs: index %u not found", indexoid); indexStruct = (Form_pg_index) GETSTRUCT(indexTuple); if (indexStruct->indisunique) { for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++) ; if (i == length(fkconstraint->pk_attrs)) { /* go through the fkconstraint->pk_attrs list */ List *attrl; int attnum = 0; foreach(attrl, fkconstraint->pk_attrs) { Ident *attr = lfirst(attrl); found = false; for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++) { int pkattno = indexStruct->indkey[i]; if (namestrcmp(attnumAttName(pkrel, pkattno), attr->name) == 0) { pktypoid[attnum++] = attnumTypeId(pkrel, pkattno); found = true; break; } } if (!found) break; } } } ReleaseSysCache(indexTuple); if (found) break; } if (!found) elog(ERROR, "UNIQUE constraint matching given keys for referenced table \"%s\" not found", fkconstraint->pktable->relname); freeList(indexoidlist); heap_close(pkrel, AccessShareLock); } /* * transformFkeyGetPrimaryKey - * * Try to find the primary key attributes of a referenced table if * the column list in the REFERENCES specification was omitted. */ static void transformFkeyGetPrimaryKey(FkConstraint *fkconstraint, Oid *pktypoid) { Relation pkrel; List *indexoidlist, *indexoidscan; HeapTuple indexTuple = NULL; Form_pg_index indexStruct = NULL; int i; int attnum = 0; /* * Open the referenced table */ pkrel = heap_openrv(fkconstraint->pktable, AccessShareLock); if (pkrel->rd_rel->relkind != RELKIND_RELATION) elog(ERROR, "Referenced relation \"%s\" is not a table", fkconstraint->pktable->relname); /* * Get the list of index OIDs for the table from the relcache, and * look up each one in the pg_index syscache until we find one marked * primary key (hopefully there isn't more than one such). */ indexoidlist = RelationGetIndexList(pkrel); foreach(indexoidscan, indexoidlist) { Oid indexoid = lfirsti(indexoidscan); indexTuple = SearchSysCache(INDEXRELID, ObjectIdGetDatum(indexoid), 0, 0, 0); if (!HeapTupleIsValid(indexTuple)) elog(ERROR, "transformFkeyGetPrimaryKey: index %u not found", indexoid); indexStruct = (Form_pg_index) GETSTRUCT(indexTuple); if (indexStruct->indisprimary) break; ReleaseSysCache(indexTuple); indexStruct = NULL; } freeList(indexoidlist); /* * Check that we found it */ if (indexStruct == NULL) elog(ERROR, "PRIMARY KEY for referenced table \"%s\" not found", fkconstraint->pktable->relname); /* * Now build the list of PK attributes from the indkey definition * using the attribute names of the PK relation descriptor */ for (i = 0; i < INDEX_MAX_KEYS && indexStruct->indkey[i] != 0; i++) { int pkattno = indexStruct->indkey[i]; Ident *pkattr = makeNode(Ident); pkattr->name = pstrdup(NameStr(*attnumAttName(pkrel, pkattno))); pktypoid[attnum++] = attnumTypeId(pkrel, pkattno); fkconstraint->pk_attrs = lappend(fkconstraint->pk_attrs, pkattr); } ReleaseSysCache(indexTuple); heap_close(pkrel, AccessShareLock); } /* * relationHasPrimaryKey - * * See whether an existing relation has a primary key. */ static bool relationHasPrimaryKey(Oid relationOid) { bool result = false; Relation rel; List *indexoidlist, *indexoidscan; rel = heap_open(relationOid, AccessShareLock); /* * Get the list of index OIDs for the table from the relcache, and * look up each one in the pg_index syscache until we find one marked * primary key (hopefully there isn't more than one such). */ indexoidlist = RelationGetIndexList(rel); foreach(indexoidscan, indexoidlist) { Oid indexoid = lfirsti(indexoidscan); HeapTuple indexTuple; indexTuple = SearchSysCache(INDEXRELID, ObjectIdGetDatum(indexoid), 0, 0, 0); if (!HeapTupleIsValid(indexTuple)) elog(ERROR, "relationHasPrimaryKey: index %u not found", indexoid); result = ((Form_pg_index) GETSTRUCT(indexTuple))->indisprimary; ReleaseSysCache(indexTuple); if (result) break; } freeList(indexoidlist); heap_close(rel, AccessShareLock); return result; } /* * transformFkeyGetColType - * * Find a referencing column by name, and return its type OID. * Error if it can't be found. */ static Oid transformFkeyGetColType(CreateStmtContext *cxt, char *colname) { List *cols; List *inher; Oid result; Form_pg_attribute sysatt; /* First look for column among the newly-created columns */ foreach(cols, cxt->columns) { ColumnDef *col = lfirst(cols); if (strcmp(col->colname, colname) == 0) return typenameTypeId(col->typename); } /* Perhaps it's a system column name */ sysatt = SystemAttributeByName(colname, cxt->hasoids); if (sysatt) return sysatt->atttypid; /* Look for column among inherited columns (if CREATE TABLE case) */ foreach(inher, cxt->inhRelations) { RangeVar *inh = lfirst(inher); Relation rel; int count; Assert(IsA(inh, RangeVar)); rel = heap_openrv(inh, AccessShareLock); if (rel->rd_rel->relkind != RELKIND_RELATION) elog(ERROR, "inherited table \"%s\" is not a relation", inh->relname); for (count = 0; count < rel->rd_att->natts; count++) { Form_pg_attribute inhattr = rel->rd_att->attrs[count]; char *inhname = NameStr(inhattr->attname); if (inhattr->attisdropped) continue; if (strcmp(inhname, colname) == 0) { result = inhattr->atttypid; heap_close(rel, NoLock); return result; } } heap_close(rel, NoLock); } /* Look for column among existing columns (if ALTER TABLE case) */ if (OidIsValid(cxt->relOid)) { HeapTuple atttuple; atttuple = SearchSysCacheAttName(cxt->relOid, colname); if (HeapTupleIsValid(atttuple)) { result = ((Form_pg_attribute) GETSTRUCT(atttuple))->atttypid; ReleaseSysCache(atttuple); return result; } } elog(ERROR, "%s: column \"%s\" referenced in foreign key constraint does not exist", cxt->stmtType, colname); return InvalidOid; /* keep compiler quiet */ } /* * Preprocess a list of column constraint clauses * to attach constraint attributes to their primary constraint nodes * and detect inconsistent/misplaced constraint attributes. * * NOTE: currently, attributes are only supported for FOREIGN KEY primary * constraints, but someday they ought to be supported for other constraints. */ static void transformConstraintAttrs(List *constraintList) { Node *lastprimarynode = NULL; bool saw_deferrability = false; bool saw_initially = false; List *clist; foreach(clist, constraintList) { Node *node = lfirst(clist); if (!IsA(node, Constraint)) { lastprimarynode = node; /* reset flags for new primary node */ saw_deferrability = false; saw_initially = false; } else { Constraint *con = (Constraint *) node; switch (con->contype) { case CONSTR_ATTR_DEFERRABLE: if (lastprimarynode == NULL || !IsA(lastprimarynode, FkConstraint)) elog(ERROR, "Misplaced DEFERRABLE clause"); if (saw_deferrability) elog(ERROR, "Multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed"); saw_deferrability = true; ((FkConstraint *) lastprimarynode)->deferrable = true; break; case CONSTR_ATTR_NOT_DEFERRABLE: if (lastprimarynode == NULL || !IsA(lastprimarynode, FkConstraint)) elog(ERROR, "Misplaced NOT DEFERRABLE clause"); if (saw_deferrability) elog(ERROR, "Multiple DEFERRABLE/NOT DEFERRABLE clauses not allowed"); saw_deferrability = true; ((FkConstraint *) lastprimarynode)->deferrable = false; if (saw_initially && ((FkConstraint *) lastprimarynode)->initdeferred) elog(ERROR, "INITIALLY DEFERRED constraint must be DEFERRABLE"); break; case CONSTR_ATTR_DEFERRED: if (lastprimarynode == NULL || !IsA(lastprimarynode, FkConstraint)) elog(ERROR, "Misplaced INITIALLY DEFERRED clause"); if (saw_initially) elog(ERROR, "Multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed"); saw_initially = true; ((FkConstraint *) lastprimarynode)->initdeferred = true; /* * If only INITIALLY DEFERRED appears, assume * DEFERRABLE */ if (!saw_deferrability) ((FkConstraint *) lastprimarynode)->deferrable = true; else if (!((FkConstraint *) lastprimarynode)->deferrable) elog(ERROR, "INITIALLY DEFERRED constraint must be DEFERRABLE"); break; case CONSTR_ATTR_IMMEDIATE: if (lastprimarynode == NULL || !IsA(lastprimarynode, FkConstraint)) elog(ERROR, "Misplaced INITIALLY IMMEDIATE clause"); if (saw_initially) elog(ERROR, "Multiple INITIALLY IMMEDIATE/DEFERRED clauses not allowed"); saw_initially = true; ((FkConstraint *) lastprimarynode)->initdeferred = false; break; default: /* Otherwise it's not an attribute */ lastprimarynode = node; /* reset flags for new primary node */ saw_deferrability = false; saw_initially = false; break; } } } } /* Build a FromExpr node */ static FromExpr * makeFromExpr(List *fromlist, Node *quals) { FromExpr *f = makeNode(FromExpr); f->fromlist = fromlist; f->quals = quals; return f; } /* * Special handling of type definition for a column */ static void transformColumnType(ParseState *pstate, ColumnDef *column) { TypeName *typename = column->typename; Type ctype = typenameType(typename); /* * Is this the name of a complex type? If so, implement it as a set. * * XXX this is a hangover from ancient Berkeley code that probably * doesn't work anymore anyway. */ if (typeTypeRelid(ctype) != InvalidOid) { /* * (Eventually add in here that the set can only contain one * element.) */ typename->setof = true; } ReleaseSysCache(ctype); } /* * analyzeCreateSchemaStmt - * analyzes the "create schema" statement * * Split the schema element list into individual commands and place * them in the result list in an order such that there are no * forward references (e.g. GRANT to a table created later in the list). * * SQL92 also allows constraints to make forward references, so thumb through * the table columns and move forward references to a posterior alter-table * command. * * The result is a list of parse nodes that still need to be analyzed --- * but we can't analyze the later commands until we've executed the earlier * ones, because of possible inter-object references. * * Note: Called from commands/command.c */ List * analyzeCreateSchemaStmt(CreateSchemaStmt *stmt) { CreateSchemaStmtContext cxt; List *result; List *elements; cxt.stmtType = "CREATE SCHEMA"; cxt.schemaname = stmt->schemaname; cxt.authid = stmt->authid; cxt.tables = NIL; cxt.views = NIL; cxt.grants = NIL; cxt.fwconstraints = NIL; cxt.alters = NIL; cxt.blist = NIL; cxt.alist = NIL; /* * Run through each schema element in the schema element list. * Separate statements by type, and do preliminary analysis. */ foreach(elements, stmt->schemaElts) { Node *element = lfirst(elements); switch (nodeTag(element)) { case T_CreateStmt: { CreateStmt *elp = (CreateStmt *) element; if (elp->relation->schemaname == NULL) elp->relation->schemaname = cxt.schemaname; else if (strcmp(cxt.schemaname, elp->relation->schemaname) != 0) elog(ERROR, "New table specifies a schema (%s)" " different from the one being created (%s)", elp->relation->schemaname, cxt.schemaname); /* * XXX todo: deal with constraints */ cxt.tables = lappend(cxt.tables, element); } break; case T_ViewStmt: { ViewStmt *elp = (ViewStmt *) element; if (elp->view->schemaname == NULL) elp->view->schemaname = cxt.schemaname; else if (strcmp(cxt.schemaname, elp->view->schemaname) != 0) elog(ERROR, "New view specifies a schema (%s)" " different from the one being created (%s)", elp->view->schemaname, cxt.schemaname); /* * XXX todo: deal with references between views */ cxt.views = lappend(cxt.views, element); } break; case T_GrantStmt: cxt.grants = lappend(cxt.grants, element); break; default: elog(ERROR, "parser: unsupported schema node (internal error)"); } } result = NIL; result = nconc(result, cxt.tables); result = nconc(result, cxt.views); result = nconc(result, cxt.grants); return result; }