/*------------------------------------------------------------------------- * * index.c * code to create and destroy POSTGRES index relations * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION * $Header: /cvsroot/pgsql/src/backend/catalog/index.c,v 1.95 1999/11/16 04:13:55 momjian Exp $ * * * INTERFACE ROUTINES * index_create() - Create a cataloged index relation * index_destroy() - Removes index relation from catalogs * * *------------------------------------------------------------------------- */ #include "postgres.h" #include "access/genam.h" #include "access/heapam.h" #include "access/istrat.h" #include "access/xact.h" #include "bootstrap/bootstrap.h" #include "catalog/catname.h" #include "catalog/heap.h" #include "catalog/index.h" #include "catalog/indexing.h" #include "catalog/pg_index.h" #include "catalog/pg_proc.h" #include "catalog/pg_type.h" #include "commands/comment.h" #include "executor/executor.h" #include "miscadmin.h" #include "optimizer/clauses.h" #include "optimizer/prep.h" #include "parser/parse_func.h" #include "storage/smgr.h" #include "utils/builtins.h" #include "utils/relcache.h" #include "utils/syscache.h" #include "utils/temprel.h" /* * macros used in guessing how many tuples are on a page. */ #define AVG_ATTR_SIZE 8 #define NTUPLES_PER_PAGE(natts) \ ((BLCKSZ - MAXALIGN(sizeof (PageHeaderData))) / \ ((natts) * AVG_ATTR_SIZE + MAXALIGN(sizeof(HeapTupleHeaderData)))) /* non-export function prototypes */ static Oid GetHeapRelationOid(char *heapRelationName, char *indexRelationName, bool istemp); static TupleDesc BuildFuncTupleDesc(FuncIndexInfo *funcInfo); static TupleDesc ConstructTupleDescriptor(Oid heapoid, Relation heapRelation, List *attributeList, int numatts, AttrNumber *attNums); static void ConstructIndexReldesc(Relation indexRelation, Oid amoid); static Oid UpdateRelationRelation(Relation indexRelation, char *temp_relname); static void InitializeAttributeOids(Relation indexRelation, int numatts, Oid indexoid); static void AppendAttributeTuples(Relation indexRelation, int numatts); static void UpdateIndexRelation(Oid indexoid, Oid heapoid, FuncIndexInfo *funcInfo, int natts, AttrNumber *attNums, Oid *classOids, Node *predicate, List *attributeList, bool islossy, bool unique, bool primary); static void DefaultBuild(Relation heapRelation, Relation indexRelation, int numberOfAttributes, AttrNumber *attributeNumber, IndexStrategy indexStrategy, uint16 parameterCount, Datum *parameter, FuncIndexInfoPtr funcInfo, PredInfo *predInfo); /* ---------------------------------------------------------------- * sysatts is a structure containing attribute tuple forms * for system attributes (numbered -1, -2, ...). This really * should be generated or eliminated or moved elsewhere. -cim 1/19/91 * * typedef struct FormData_pg_attribute { * Oid attrelid; * NameData attname; * Oid atttypid; * uint32 attnvals; * int16 attlen; * AttrNumber attnum; * uint32 attnelems; * int32 attcacheoff; * int32 atttypmod; * bool attbyval; * bool attisset; * char attalign; * bool attnotnull; * bool atthasdef; * } FormData_pg_attribute; * * ---------------------------------------------------------------- */ static FormData_pg_attribute sysatts[] = { {0, {"ctid"}, TIDOID, 0, 6, -1, 0, -1, -1, '\0', '\0', 'i', '\0', '\0'}, {0, {"oid"}, OIDOID, 0, 4, -2, 0, -1, -1, '\001', '\0', 'i', '\0', '\0'}, {0, {"xmin"}, XIDOID, 0, 4, -3, 0, -1, -1, '\001', '\0', 'i', '\0', '\0'}, {0, {"cmin"}, CIDOID, 0, 4, -4, 0, -1, -1, '\001', '\0', 'i', '\0', '\0'}, {0, {"xmax"}, XIDOID, 0, 4, -5, 0, -1, -1, '\001', '\0', 'i', '\0', '\0'}, {0, {"cmax"}, CIDOID, 0, 4, -6, 0, -1, -1, '\001', '\0', 'i', '\0', '\0'}, }; /* ---------------------------------------------------------------- * GetHeapRelationOid * ---------------------------------------------------------------- */ static Oid GetHeapRelationOid(char *heapRelationName, char *indexRelationName, bool istemp) { Oid indoid; Oid heapoid; indoid = RelnameFindRelid(indexRelationName); if ((!istemp && OidIsValid(indoid)) || (istemp && get_temp_rel_by_username(indexRelationName) != NULL)) elog(ERROR, "Cannot create index: '%s' already exists", indexRelationName); heapoid = RelnameFindRelid(heapRelationName); if (!OidIsValid(heapoid)) elog(ERROR, "Cannot create index on '%s': relation does not exist", heapRelationName); return heapoid; } static TupleDesc BuildFuncTupleDesc(FuncIndexInfo *funcInfo) { HeapTuple tuple; TupleDesc funcTupDesc; Oid retType; char *funcname; int4 nargs; Oid *argtypes; /* * Allocate and zero a tuple descriptor. */ funcTupDesc = CreateTemplateTupleDesc(1); funcTupDesc->attrs[0] = (Form_pg_attribute) palloc(ATTRIBUTE_TUPLE_SIZE); MemSet(funcTupDesc->attrs[0], 0, ATTRIBUTE_TUPLE_SIZE); /* * Lookup the function for the return type. */ funcname = FIgetname(funcInfo); nargs = FIgetnArgs(funcInfo); argtypes = FIgetArglist(funcInfo); tuple = SearchSysCacheTuple(PRONAME, PointerGetDatum(funcname), Int32GetDatum(nargs), PointerGetDatum(argtypes), 0); if (!HeapTupleIsValid(tuple)) func_error("BuildFuncTupleDesc", funcname, nargs, argtypes, NULL); retType = ((Form_pg_proc) GETSTRUCT(tuple))->prorettype; /* * Look up the return type in pg_type for the type length. */ tuple = SearchSysCacheTuple(TYPOID, ObjectIdGetDatum(retType), 0, 0, 0); if (!HeapTupleIsValid(tuple)) elog(ERROR, "Function %s return type does not exist", FIgetname(funcInfo)); /* * Assign some of the attributes values. Leave the rest as 0. */ funcTupDesc->attrs[0]->attlen = ((Form_pg_type) GETSTRUCT(tuple))->typlen; funcTupDesc->attrs[0]->atttypid = retType; funcTupDesc->attrs[0]->attnum = 1; funcTupDesc->attrs[0]->attbyval = ((Form_pg_type) GETSTRUCT(tuple))->typbyval; funcTupDesc->attrs[0]->attcacheoff = -1; funcTupDesc->attrs[0]->atttypmod = -1; funcTupDesc->attrs[0]->attalign = ((Form_pg_type) GETSTRUCT(tuple))->typalign; /* * make the attributes name the same as the functions */ namestrcpy(&funcTupDesc->attrs[0]->attname, funcname); return funcTupDesc; } /* ---------------------------------------------------------------- * ConstructTupleDescriptor * ---------------------------------------------------------------- */ static TupleDesc ConstructTupleDescriptor(Oid heapoid, Relation heapRelation, List *attributeList, int numatts, AttrNumber *attNums) { TupleDesc heapTupDesc; TupleDesc indexTupDesc; IndexElem *IndexKey; TypeName *IndexKeyType; AttrNumber atnum; /* attributeNumber[attributeOffset] */ AttrNumber atind; int natts; /* Form_pg_class->relnatts */ char *from; /* used to simplify memcpy below */ char *to; /* used to simplify memcpy below */ int i; /* ---------------- * allocate the new tuple descriptor * ---------------- */ natts = RelationGetForm(heapRelation)->relnatts; indexTupDesc = CreateTemplateTupleDesc(numatts); /* ---------------- * * ---------------- */ /* ---------------- * for each attribute we are indexing, obtain its attribute * tuple form from either the static table of system attribute * tuple forms or the relation tuple descriptor * ---------------- */ for (i = 0; i < numatts; i += 1) { /* ---------------- * get the attribute number and make sure it's valid * ---------------- */ atnum = attNums[i]; if (atnum > natts) elog(ERROR, "Cannot create index: attribute %d does not exist", atnum); if (attributeList) { IndexKey = (IndexElem *) lfirst(attributeList); IndexKeyType = IndexKey->typename; attributeList = lnext(attributeList); } else IndexKeyType = NULL; indexTupDesc->attrs[i] = (Form_pg_attribute) palloc(ATTRIBUTE_TUPLE_SIZE); /* ---------------- * determine which tuple descriptor to copy * ---------------- */ if (!AttrNumberIsForUserDefinedAttr(atnum)) { /* ---------------- * here we are indexing on a system attribute (-1...-12) * so we convert atnum into a usable index 0...11 so we can * use it to dereference the array sysatts[] which stores * tuple descriptor information for system attributes. * ---------------- */ if (atnum <= FirstLowInvalidHeapAttributeNumber || atnum >= 0) elog(ERROR, "Cannot create index on system attribute: attribute number out of range (%d)", atnum); atind = (-atnum) - 1; from = (char *) (&sysatts[atind]); } else { /* ---------------- * here we are indexing on a normal attribute (1...n) * ---------------- */ heapTupDesc = RelationGetDescr(heapRelation); atind = AttrNumberGetAttrOffset(atnum); from = (char *) (heapTupDesc->attrs[atind]); } /* ---------------- * now that we've determined the "from", let's copy * the tuple desc data... * ---------------- */ to = (char *) (indexTupDesc->attrs[i]); memcpy(to, from, ATTRIBUTE_TUPLE_SIZE); ((Form_pg_attribute) to)->attnum = i + 1; ((Form_pg_attribute) to)->attnotnull = false; ((Form_pg_attribute) to)->atthasdef = false; ((Form_pg_attribute) to)->attcacheoff = -1; ((Form_pg_attribute) to)->atttypmod = -1; ((Form_pg_attribute) to)->attalign = 'i'; /* * if the keytype is defined, we need to change the tuple form's * atttypid & attlen field to match that of the key's type */ if (IndexKeyType != NULL) { HeapTuple tup; tup = SearchSysCacheTuple(TYPNAME, PointerGetDatum(IndexKeyType->name), 0, 0, 0); if (!HeapTupleIsValid(tup)) elog(ERROR, "create index: type '%s' undefined", IndexKeyType->name); ((Form_pg_attribute) to)->atttypid = tup->t_data->t_oid; ((Form_pg_attribute) to)->attbyval = ((Form_pg_type) GETSTRUCT(tup))->typbyval; ((Form_pg_attribute) to)->attlen = ((Form_pg_type) GETSTRUCT(tup))->typlen; ((Form_pg_attribute) to)->attalign = ((Form_pg_type) GETSTRUCT(tup))->typalign; ((Form_pg_attribute) to)->atttypmod = IndexKeyType->typmod; } /* ---------------- * now we have to drop in the proper relation descriptor * into the copied tuple form's attrelid and we should be * all set. * ---------------- */ ((Form_pg_attribute) to)->attrelid = heapoid; } return indexTupDesc; } /* ---------------------------------------------------------------- * AccessMethodObjectIdGetForm * Returns the formated access method tuple given its object identifier. * * XXX ADD INDEXING * * Note: * Assumes object identifier is valid. * ---------------------------------------------------------------- */ Form_pg_am AccessMethodObjectIdGetForm(Oid accessMethodObjectId) { Relation pg_am_desc; HeapScanDesc pg_am_scan; HeapTuple pg_am_tuple; ScanKeyData key; Form_pg_am aform; /* ---------------- * form a scan key for the pg_am relation * ---------------- */ ScanKeyEntryInitialize(&key, 0, ObjectIdAttributeNumber, F_OIDEQ, ObjectIdGetDatum(accessMethodObjectId)); /* ---------------- * fetch the desired access method tuple * ---------------- */ pg_am_desc = heap_openr(AccessMethodRelationName, AccessShareLock); pg_am_scan = heap_beginscan(pg_am_desc, 0, SnapshotNow, 1, &key); pg_am_tuple = heap_getnext(pg_am_scan, 0); /* ---------------- * return NULL if not found * ---------------- */ if (!HeapTupleIsValid(pg_am_tuple)) { heap_endscan(pg_am_scan); heap_close(pg_am_desc, AccessShareLock); return NULL; } /* ---------------- * if found am tuple, then copy the form and return the copy * ---------------- */ aform = (Form_pg_am) palloc(sizeof *aform); memcpy(aform, GETSTRUCT(pg_am_tuple), sizeof *aform); heap_endscan(pg_am_scan); heap_close(pg_am_desc, AccessShareLock); return aform; } /* ---------------------------------------------------------------- * ConstructIndexReldesc * ---------------------------------------------------------------- */ static void ConstructIndexReldesc(Relation indexRelation, Oid amoid) { extern GlobalMemory CacheCxt; MemoryContext oldcxt; /* ---------------- * here we make certain to allocate the access method * tuple within the cache context lest it vanish when the * context changes * ---------------- */ if (!CacheCxt) CacheCxt = CreateGlobalMemory("Cache"); oldcxt = MemoryContextSwitchTo((MemoryContext) CacheCxt); indexRelation->rd_am = AccessMethodObjectIdGetForm(amoid); MemoryContextSwitchTo(oldcxt); /* ---------------- * XXX missing the initialization of some other fields * ---------------- */ indexRelation->rd_rel->relowner = GetUserId(); indexRelation->rd_rel->relam = amoid; indexRelation->rd_rel->reltuples = 1; /* XXX */ indexRelation->rd_rel->relkind = RELKIND_INDEX; } /* ---------------------------------------------------------------- * UpdateRelationRelation * ---------------------------------------------------------------- */ static Oid UpdateRelationRelation(Relation indexRelation, char *temp_relname) { Relation pg_class; HeapTuple tuple; Oid tupleOid; Relation idescs[Num_pg_class_indices]; pg_class = heap_openr(RelationRelationName, RowExclusiveLock); /* XXX Natts_pg_class_fixed is a hack - see pg_class.h */ tuple = heap_addheader(Natts_pg_class_fixed, sizeof(*indexRelation->rd_rel), (char *) indexRelation->rd_rel); /* ---------------- * the new tuple must have the same oid as the relcache entry for the * index. sure would be embarassing to do this sort of thing in polite * company. * ---------------- */ tuple->t_data->t_oid = RelationGetRelid(indexRelation); heap_insert(pg_class, tuple); if (temp_relname) create_temp_relation(temp_relname, tuple); /* * During normal processing, we need to make sure that the system * catalog indices are correct. Bootstrap (initdb) time doesn't * require this, because we make sure that the indices are correct * just before exiting. */ if (!IsBootstrapProcessingMode()) { CatalogOpenIndices(Num_pg_class_indices, Name_pg_class_indices, idescs); CatalogIndexInsert(idescs, Num_pg_class_indices, pg_class, tuple); CatalogCloseIndices(Num_pg_class_indices, idescs); } tupleOid = tuple->t_data->t_oid; pfree(tuple); heap_close(pg_class, RowExclusiveLock); return tupleOid; } /* ---------------------------------------------------------------- * InitializeAttributeOids * ---------------------------------------------------------------- */ static void InitializeAttributeOids(Relation indexRelation, int numatts, Oid indexoid) { TupleDesc tupleDescriptor; int i; tupleDescriptor = RelationGetDescr(indexRelation); for (i = 0; i < numatts; i += 1) tupleDescriptor->attrs[i]->attrelid = indexoid; } /* ---------------------------------------------------------------- * AppendAttributeTuples * * XXX For now, only change the ATTNUM attribute value * ---------------------------------------------------------------- */ static void AppendAttributeTuples(Relation indexRelation, int numatts) { Relation pg_attribute; HeapTuple init_tuple, cur_tuple = NULL, new_tuple; bool hasind; Relation idescs[Num_pg_attr_indices]; Datum value[Natts_pg_attribute]; char nullv[Natts_pg_attribute]; char replace[Natts_pg_attribute]; TupleDesc indexTupDesc; int i; /* ---------------- * open the attribute relation * XXX ADD INDEXING * ---------------- */ pg_attribute = heap_openr(AttributeRelationName, RowExclusiveLock); /* ---------------- * initialize *null, *replace and *value * ---------------- */ MemSet(nullv, ' ', Natts_pg_attribute); MemSet(replace, ' ', Natts_pg_attribute); /* ---------------- * create the first attribute tuple. * XXX For now, only change the ATTNUM attribute value * ---------------- */ replace[Anum_pg_attribute_attnum - 1] = 'r'; replace[Anum_pg_attribute_attcacheoff - 1] = 'r'; value[Anum_pg_attribute_attnum - 1] = Int16GetDatum(1); value[Anum_pg_attribute_attcacheoff - 1] = Int32GetDatum(-1); init_tuple = heap_addheader(Natts_pg_attribute, ATTRIBUTE_TUPLE_SIZE, (char *) (indexRelation->rd_att->attrs[0])); hasind = false; if (!IsBootstrapProcessingMode() && pg_attribute->rd_rel->relhasindex) { hasind = true; CatalogOpenIndices(Num_pg_attr_indices, Name_pg_attr_indices, idescs); } /* ---------------- * insert the first attribute tuple. * ---------------- */ cur_tuple = heap_modifytuple(init_tuple, pg_attribute, value, nullv, replace); pfree(init_tuple); heap_insert(pg_attribute, cur_tuple); if (hasind) CatalogIndexInsert(idescs, Num_pg_attr_indices, pg_attribute, cur_tuple); /* ---------------- * now we use the information in the index cur_tuple * descriptor to form the remaining attribute tuples. * ---------------- */ indexTupDesc = RelationGetDescr(indexRelation); for (i = 1; i < numatts; i += 1) { /* ---------------- * process the remaining attributes... * ---------------- */ memmove(GETSTRUCT(cur_tuple), (char *) indexTupDesc->attrs[i], ATTRIBUTE_TUPLE_SIZE); value[Anum_pg_attribute_attnum - 1] = Int16GetDatum(i + 1); new_tuple = heap_modifytuple(cur_tuple, pg_attribute, value, nullv, replace); pfree(cur_tuple); heap_insert(pg_attribute, new_tuple); if (hasind) CatalogIndexInsert(idescs, Num_pg_attr_indices, pg_attribute, new_tuple); /* ---------------- * ModifyHeapTuple returns a new copy of a cur_tuple * so we free the original and use the copy.. * ---------------- */ cur_tuple = new_tuple; } if (cur_tuple) pfree(cur_tuple); heap_close(pg_attribute, RowExclusiveLock); if (hasind) CatalogCloseIndices(Num_pg_attr_indices, idescs); } /* ---------------------------------------------------------------- * UpdateIndexRelation * ---------------------------------------------------------------- */ static void UpdateIndexRelation(Oid indexoid, Oid heapoid, FuncIndexInfo *funcInfo, int natts, AttrNumber *attNums, Oid *classOids, Node *predicate, List *attributeList, bool islossy, bool unique, bool primary) { Form_pg_index indexForm; IndexElem *IndexKey; char *predString; text *predText; int predLen, itupLen; Relation pg_index; HeapTuple tuple; int i; Relation idescs[Num_pg_index_indices]; /* ---------------- * allocate an Form_pg_index big enough to hold the * index-predicate (if any) in string form * ---------------- */ if (predicate != NULL) { predString = nodeToString(predicate); predText = (text *) fmgr(F_TEXTIN, predString); pfree(predString); } else predText = (text *) fmgr(F_TEXTIN, ""); predLen = VARSIZE(predText); itupLen = predLen + sizeof(FormData_pg_index); indexForm = (Form_pg_index) palloc(itupLen); memset(indexForm, 0, sizeof(FormData_pg_index)); memmove((char *) &indexForm->indpred, (char *) predText, predLen); /* ---------------- * store the oid information into the index tuple form * ---------------- */ indexForm->indrelid = heapoid; indexForm->indexrelid = indexoid; indexForm->indproc = (PointerIsValid(funcInfo)) ? FIgetProcOid(funcInfo) : InvalidOid; indexForm->indislossy = islossy; indexForm->indisprimary = primary; indexForm->indisunique = unique; indexForm->indhaskeytype = 0; while (attributeList != NIL) { IndexKey = (IndexElem *) lfirst(attributeList); if (IndexKey->typename != NULL) { indexForm->indhaskeytype = 1; break; } attributeList = lnext(attributeList); } MemSet((char *) &indexForm->indkey[0], 0, sizeof indexForm->indkey); MemSet((char *) &indexForm->indclass[0], 0, sizeof indexForm->indclass); /* ---------------- * copy index key and op class information * ---------------- */ for (i = 0; i < natts; i += 1) { indexForm->indkey[i] = attNums[i]; indexForm->indclass[i] = classOids[i]; } /* * If we have a functional index, add all attribute arguments */ if (PointerIsValid(funcInfo)) { for (i = 1; i < FIgetnArgs(funcInfo); i++) indexForm->indkey[i] = attNums[i]; } indexForm->indisclustered = '\0'; /* XXX constant */ /* ---------------- * open the system catalog index relation * ---------------- */ pg_index = heap_openr(IndexRelationName, RowExclusiveLock); /* ---------------- * form a tuple to insert into pg_index * ---------------- */ tuple = heap_addheader(Natts_pg_index, itupLen, (char *) indexForm); /* ---------------- * insert the tuple into the pg_index * XXX ADD INDEX TUPLES TOO * ---------------- */ heap_insert(pg_index, tuple); /* ---------------- * insert the index tuple into the pg_index * ---------------- */ if (!IsBootstrapProcessingMode()) { CatalogOpenIndices(Num_pg_index_indices, Name_pg_index_indices, idescs); CatalogIndexInsert(idescs, Num_pg_index_indices, pg_index, tuple); CatalogCloseIndices(Num_pg_index_indices, idescs); } /* ---------------- * close the relation and free the tuple * ---------------- */ heap_close(pg_index, RowExclusiveLock); pfree(predText); pfree(indexForm); pfree(tuple); } /* ---------------------------------------------------------------- * UpdateIndexPredicate * ---------------------------------------------------------------- */ void UpdateIndexPredicate(Oid indexoid, Node *oldPred, Node *predicate) { Node *newPred; char *predString; text *predText; Relation pg_index; HeapTuple tuple; HeapTuple newtup; int i; Datum values[Natts_pg_index]; char nulls[Natts_pg_index]; char replace[Natts_pg_index]; /* * Construct newPred as a CNF expression equivalent to the OR of the * original partial-index predicate ("oldPred") and the extension * predicate ("predicate"). * * This should really try to process the result to change things like * "a>2 OR a>1" to simply "a>1", but for now all it does is make sure * that if the extension predicate is NULL (i.e., it is being extended * to be a complete index), then newPred will be NULL - in effect, * changing "a>2 OR TRUE" to "TRUE". --Nels, Jan '93 */ newPred = NULL; if (predicate != NULL) { newPred = (Node *) make_orclause(lcons(make_andclause((List *) predicate), lcons(make_andclause((List *) oldPred), NIL))); newPred = (Node *) cnfify((Expr *) newPred, true); } /* translate the index-predicate to string form */ if (newPred != NULL) { predString = nodeToString(newPred); predText = (text *) fmgr(F_TEXTIN, predString); pfree(predString); } else predText = (text *) fmgr(F_TEXTIN, ""); /* open the index system catalog relation */ pg_index = heap_openr(IndexRelationName, RowExclusiveLock); tuple = SearchSysCacheTuple(INDEXRELID, ObjectIdGetDatum(indexoid), 0, 0, 0); Assert(HeapTupleIsValid(tuple)); for (i = 0; i < Natts_pg_index; i++) { nulls[i] = heap_attisnull(tuple, i + 1) ? 'n' : ' '; replace[i] = ' '; values[i] = (Datum) NULL; } replace[Anum_pg_index_indpred - 1] = 'r'; values[Anum_pg_index_indpred - 1] = (Datum) predText; newtup = heap_modifytuple(tuple, pg_index, values, nulls, replace); heap_replace(pg_index, &newtup->t_self, newtup, NULL); pfree(newtup); heap_close(pg_index, RowExclusiveLock); pfree(predText); } /* ---------------------------------------------------------------- * InitIndexStrategy * ---------------------------------------------------------------- */ void InitIndexStrategy(int numatts, Relation indexRelation, Oid accessMethodObjectId) { IndexStrategy strategy; RegProcedure *support; uint16 amstrategies; uint16 amsupport; Oid attrelid; Size strsize; extern GlobalMemory CacheCxt; /* ---------------- * get information from the index relation descriptor * ---------------- */ attrelid = indexRelation->rd_att->attrs[0]->attrelid; amstrategies = indexRelation->rd_am->amstrategies; amsupport = indexRelation->rd_am->amsupport; /* ---------------- * get the size of the strategy * ---------------- */ strsize = AttributeNumberGetIndexStrategySize(numatts, amstrategies); /* ---------------- * allocate the new index strategy structure * * the index strategy has to be allocated in the same * context as the relation descriptor cache or else * it will be lost at the end of the transaction. * ---------------- */ if (!CacheCxt) CacheCxt = CreateGlobalMemory("Cache"); strategy = (IndexStrategy) MemoryContextAlloc((MemoryContext) CacheCxt, strsize); if (amsupport > 0) { strsize = numatts * (amsupport * sizeof(RegProcedure)); support = (RegProcedure *) MemoryContextAlloc((MemoryContext) CacheCxt, strsize); } else support = (RegProcedure *) NULL; /* ---------------- * fill in the index strategy structure with information * from the catalogs. Note: we use heap override mode * in order to be allowed to see the correct information in the * catalogs, even though our transaction has not yet committed. * ---------------- */ setheapoverride(true); IndexSupportInitialize(strategy, support, attrelid, accessMethodObjectId, amstrategies, amsupport, numatts); setheapoverride(false); /* ---------------- * store the strategy information in the index reldesc * ---------------- */ RelationSetIndexSupport(indexRelation, strategy, support); } /* ---------------------------------------------------------------- * index_create * ---------------------------------------------------------------- */ void index_create(char *heapRelationName, char *indexRelationName, FuncIndexInfo *funcInfo, List *attributeList, Oid accessMethodObjectId, int numatts, AttrNumber *attNums, Oid *classObjectId, uint16 parameterCount, Datum *parameter, Node *predicate, bool islossy, bool unique, bool primary) { Relation heapRelation; Relation indexRelation; TupleDesc indexTupDesc; Oid heapoid; Oid indexoid; PredInfo *predInfo; bool istemp = (get_temp_rel_by_username(heapRelationName) != NULL); char *temp_relname = NULL; /* ---------------- * check parameters * ---------------- */ if (numatts < 1) elog(ERROR, "must index at least one attribute"); /* ---------------- * get heap relation oid and open the heap relation * XXX ADD INDEXING * ---------------- */ heapoid = GetHeapRelationOid(heapRelationName, indexRelationName, istemp); /* * Only SELECT ... FOR UPDATE are allowed while doing this */ heapRelation = heap_open(heapoid, ShareLock); /* ---------------- * construct new tuple descriptor * ---------------- */ if (PointerIsValid(funcInfo)) indexTupDesc = BuildFuncTupleDesc(funcInfo); else indexTupDesc = ConstructTupleDescriptor(heapoid, heapRelation, attributeList, numatts, attNums); /* save user relation name because heap_create changes it */ if (istemp) { temp_relname = pstrdup(indexRelationName); /* save original value */ indexRelationName = palloc(NAMEDATALEN); strcpy(indexRelationName, temp_relname); /* heap_create will * change this */ } /* ---------------- * create the index relation * ---------------- */ indexRelation = heap_create(indexRelationName, indexTupDesc, false, istemp, false); /* ---------------- * construct the index relation descriptor * * XXX should have a proper way to create cataloged relations * ---------------- */ ConstructIndexReldesc(indexRelation, accessMethodObjectId); /* ---------------- * add index to catalogs * (append RELATION tuple) * ---------------- */ indexoid = UpdateRelationRelation(indexRelation, temp_relname); /* * We create the disk file for this relation here */ heap_storage_create(indexRelation); /* ---------------- * Now get the index procedure (only relevant for functional indices). * ---------------- */ if (PointerIsValid(funcInfo)) { HeapTuple proc_tup; proc_tup = SearchSysCacheTuple(PRONAME, PointerGetDatum(FIgetname(funcInfo)), Int32GetDatum(FIgetnArgs(funcInfo)), PointerGetDatum(FIgetArglist(funcInfo)), 0); if (!HeapTupleIsValid(proc_tup)) { func_error("index_create", FIgetname(funcInfo), FIgetnArgs(funcInfo), FIgetArglist(funcInfo), NULL); } FIgetProcOid(funcInfo) = proc_tup->t_data->t_oid; } /* ---------------- * now update the object id's of all the attribute * tuple forms in the index relation's tuple descriptor * ---------------- */ InitializeAttributeOids(indexRelation, numatts, indexoid); /* ---------------- * append ATTRIBUTE tuples * ---------------- */ AppendAttributeTuples(indexRelation, numatts); /* ---------------- * update pg_index * (append INDEX tuple) * * Note that this stows away a representation of "predicate". * (Or, could define a rule to maintain the predicate) --Nels, Feb '92 * ---------------- */ UpdateIndexRelation(indexoid, heapoid, funcInfo, numatts, attNums, classObjectId, predicate, attributeList, islossy, unique, primary); predInfo = (PredInfo *) palloc(sizeof(PredInfo)); predInfo->pred = predicate; predInfo->oldPred = NULL; /* ---------------- * initialize the index strategy * ---------------- */ InitIndexStrategy(numatts, indexRelation, accessMethodObjectId); /* * If this is bootstrap (initdb) time, then we don't actually fill in * the index yet. We'll be creating more indices and classes later, * so we delay filling them in until just before we're done with * bootstrapping. Otherwise, we call the routine that constructs the * index. * * In normal processing mode, the heap and index relations are closed * by index_build() --- but we continue to hold the ShareLock on the * heap that we acquired above, until end of transaction. */ if (IsBootstrapProcessingMode()) { index_register(heapRelationName, indexRelationName, numatts, attNums, parameterCount, parameter, funcInfo, predInfo); /* XXX shouldn't we close the heap and index rels here? */ } else { index_build(heapRelation, indexRelation, numatts, attNums, parameterCount, parameter, funcInfo, predInfo); } } /* ---------------------------------------------------------------- * * index_destroy * * ---------------------------------------------------------------- */ void index_destroy(Oid indexId) { Relation userindexRelation; Relation indexRelation; Relation relationRelation; Relation attributeRelation; HeapTuple tuple; int16 attnum; Assert(OidIsValid(indexId)); userindexRelation = index_open(indexId); /* * Get exclusive lock to ensure no one else is scanning this index. */ LockRelation(userindexRelation, AccessExclusiveLock); /* ---------------- * DROP INDEX within a transaction block is dangerous, because * if the transaction is later rolled back there will be no way to * undo the unlink of the relation's physical file. For now, allow it * but emit a warning message. * Someday we might want to consider postponing the physical unlink * until transaction commit, but that's a lot of work... * The only case that actually works right is for relations created * in the current transaction, since the post-abort state would be that * they don't exist anyway. So, no warning in that case. * ---------------- */ if (IsTransactionBlock() && ! userindexRelation->rd_myxactonly) elog(NOTICE, "Caution: DROP INDEX cannot be rolled back, so don't abort now"); /* ---------------- * fix DESCRIPTION relation * ---------------- */ DeleteComments(indexId); /* ---------------- * fix RELATION relation * ---------------- */ relationRelation = heap_openr(RelationRelationName, RowExclusiveLock); tuple = SearchSysCacheTupleCopy(RELOID, ObjectIdGetDatum(indexId), 0, 0, 0); Assert(HeapTupleIsValid(tuple)); heap_delete(relationRelation, &tuple->t_self, NULL); pfree(tuple); heap_close(relationRelation, RowExclusiveLock); /* ---------------- * fix ATTRIBUTE relation * ---------------- */ attributeRelation = heap_openr(AttributeRelationName, RowExclusiveLock); attnum = 1; /* indexes start at 1 */ while (HeapTupleIsValid(tuple = SearchSysCacheTupleCopy(ATTNUM, ObjectIdGetDatum(indexId), Int16GetDatum(attnum), 0, 0))) { heap_delete(attributeRelation, &tuple->t_self, NULL); pfree(tuple); attnum++; } heap_close(attributeRelation, RowExclusiveLock); /* ---------------- * fix INDEX relation * ---------------- */ indexRelation = heap_openr(IndexRelationName, RowExclusiveLock); tuple = SearchSysCacheTupleCopy(INDEXRELID, ObjectIdGetDatum(indexId), 0, 0, 0); Assert(HeapTupleIsValid(tuple)); heap_delete(indexRelation, &tuple->t_self, NULL); pfree(tuple); heap_close(indexRelation, RowExclusiveLock); /* * flush cache and physically remove the file */ ReleaseRelationBuffers(userindexRelation); if (smgrunlink(DEFAULT_SMGR, userindexRelation) != SM_SUCCESS) elog(ERROR, "index_destroy: unlink: %m"); index_close(userindexRelation); RelationForgetRelation(indexId); /* does something only if it is a temp index */ remove_temp_relation(indexId); } /* ---------------------------------------------------------------- * index_build support * ---------------------------------------------------------------- */ /* ---------------- * FormIndexDatum * ---------------- */ void FormIndexDatum(int numberOfAttributes, AttrNumber *attributeNumber, HeapTuple heapTuple, TupleDesc heapDescriptor, Datum *datum, char *nullv, FuncIndexInfoPtr fInfo) { AttrNumber i; int offset; bool isNull; /* ---------------- * for each attribute we need from the heap tuple, * get the attribute and stick it into the datum and * null arrays. * ---------------- */ for (i = 1; i <= numberOfAttributes; i++) { offset = AttrNumberGetAttrOffset(i); datum[offset] = PointerGetDatum(GetIndexValue(heapTuple, heapDescriptor, offset, attributeNumber, fInfo, &isNull)); nullv[offset] = (isNull) ? 'n' : ' '; } } /* ---------------- * UpdateStats * ---------------- */ void UpdateStats(Oid relid, long reltuples, bool hasindex) { Relation whichRel; Relation pg_class; HeapTuple tuple; HeapTuple newtup; long relpages; int i; Form_pg_class rd_rel; Relation idescs[Num_pg_class_indices]; Datum values[Natts_pg_class]; char nulls[Natts_pg_class]; char replace[Natts_pg_class]; HeapScanDesc pg_class_scan = NULL; /* ---------------- * This routine handles updates for both the heap and index relation * statistics. In order to guarantee that we're able to *see* the index * relation tuple, we bump the command counter id here. The index * relation tuple was created in the current transaction. * ---------------- */ CommandCounterIncrement(); /* ---------------- * CommandCounterIncrement() flushes invalid cache entries, including * those for the heap and index relations for which we're updating * statistics. Now that the cache is flushed, it's safe to open the * relation again. We need the relation open in order to figure out * how many blocks it contains. * ---------------- */ /* * Can't use heap_open here since we don't know if it's an index... */ whichRel = RelationIdGetRelation(relid); if (!RelationIsValid(whichRel)) elog(ERROR, "UpdateStats: cannot open relation id %u", relid); LockRelation(whichRel, ShareLock); /* ---------------- * Find the RELATION relation tuple for the given relation. * ---------------- */ pg_class = heap_openr(RelationRelationName, RowExclusiveLock); if (!RelationIsValid(pg_class)) elog(ERROR, "UpdateStats: could not open RELATION relation"); if (!IsBootstrapProcessingMode()) { tuple = SearchSysCacheTupleCopy(RELOID, ObjectIdGetDatum(relid), 0, 0, 0); } else { ScanKeyData key[1]; ScanKeyEntryInitialize(&key[0], 0, ObjectIdAttributeNumber, F_OIDEQ, ObjectIdGetDatum(relid)); pg_class_scan = heap_beginscan(pg_class, 0, SnapshotNow, 1, key); tuple = heap_getnext(pg_class_scan, 0); } if (!HeapTupleIsValid(tuple)) { if (IsBootstrapProcessingMode()) heap_endscan(pg_class_scan); heap_close(pg_class, RowExclusiveLock); elog(ERROR, "UpdateStats: cannot scan RELATION relation"); } /* ---------------- * Figure values to insert. * * If we found zero tuples in the scan, do NOT believe it; instead put * a bogus estimate into the statistics fields. Otherwise, the common * pattern "CREATE TABLE; CREATE INDEX; insert data" leaves the table * with zero size statistics until a VACUUM is done. The optimizer will * generate very bad plans if the stats claim the table is empty when * it is actually sizable. See also CREATE TABLE in heap.c. * ---------------- */ relpages = RelationGetNumberOfBlocks(whichRel); if (reltuples == 0) { if (relpages == 0) { /* Bogus defaults for a virgin table, same as heap.c */ reltuples = 1000; relpages = 10; } else if (whichRel->rd_rel->relkind == RELKIND_INDEX && relpages <= 2) { /* Empty index, leave bogus defaults in place */ reltuples = 1000; } else reltuples = relpages * NTUPLES_PER_PAGE(whichRel->rd_rel->relnatts); } /* * We shouldn't have to do this, but we do... Modify the reldesc in * place with the new values so that the cache contains the latest * copy. */ whichRel->rd_rel->relhasindex = hasindex; whichRel->rd_rel->relpages = relpages; whichRel->rd_rel->reltuples = reltuples; /* ---------------- * Update statistics in pg_class. * ---------------- */ if (IsBootstrapProcessingMode()) { /* * At bootstrap time, we don't need to worry about concurrency or * visibility of changes, so we cheat. */ rd_rel = (Form_pg_class) GETSTRUCT(tuple); rd_rel->relpages = relpages; rd_rel->reltuples = reltuples; rd_rel->relhasindex = hasindex; WriteNoReleaseBuffer(pg_class_scan->rs_cbuf); } else { /* During normal processing, must work harder. */ for (i = 0; i < Natts_pg_class; i++) { nulls[i] = heap_attisnull(tuple, i + 1) ? 'n' : ' '; replace[i] = ' '; values[i] = (Datum) NULL; } replace[Anum_pg_class_relpages - 1] = 'r'; values[Anum_pg_class_relpages - 1] = (Datum) relpages; replace[Anum_pg_class_reltuples - 1] = 'r'; values[Anum_pg_class_reltuples - 1] = (Datum) reltuples; replace[Anum_pg_class_relhasindex - 1] = 'r'; values[Anum_pg_class_relhasindex - 1] = CharGetDatum(hasindex); newtup = heap_modifytuple(tuple, pg_class, values, nulls, replace); heap_replace(pg_class, &tuple->t_self, newtup, NULL); CatalogOpenIndices(Num_pg_class_indices, Name_pg_class_indices, idescs); CatalogIndexInsert(idescs, Num_pg_class_indices, pg_class, newtup); CatalogCloseIndices(Num_pg_class_indices, idescs); pfree(newtup); } if (!IsBootstrapProcessingMode()) pfree(tuple); else heap_endscan(pg_class_scan); heap_close(pg_class, RowExclusiveLock); /* Cheating a little bit since we didn't open it with heap_open... */ heap_close(whichRel, ShareLock); } /* ------------------------- * FillDummyExprContext * Sets up dummy ExprContext and TupleTableSlot objects for use * with ExecQual. * * NOTE: buffer is passed for historical reasons; it should * almost certainly always be InvalidBuffer. * ------------------------- */ void FillDummyExprContext(ExprContext *econtext, TupleTableSlot *slot, TupleDesc tupdesc, Buffer buffer) { econtext->ecxt_scantuple = slot; econtext->ecxt_innertuple = NULL; econtext->ecxt_outertuple = NULL; econtext->ecxt_param_list_info = NULL; econtext->ecxt_range_table = NULL; slot->ttc_tupleDescriptor = tupdesc; slot->ttc_buffer = buffer; slot->ttc_shouldFree = false; } /* ---------------- * DefaultBuild * ---------------- */ static void DefaultBuild(Relation heapRelation, Relation indexRelation, int numberOfAttributes, AttrNumber *attributeNumber, IndexStrategy indexStrategy, /* not used */ uint16 parameterCount, /* not used */ Datum *parameter, /* not used */ FuncIndexInfoPtr funcInfo, PredInfo *predInfo) { HeapScanDesc scan; HeapTuple heapTuple; IndexTuple indexTuple; TupleDesc heapDescriptor; TupleDesc indexDescriptor; Datum *datum; char *nullv; long reltuples, indtuples; #ifndef OMIT_PARTIAL_INDEX ExprContext *econtext; TupleTable tupleTable; TupleTableSlot *slot; #endif Node *predicate; Node *oldPred; InsertIndexResult insertResult; /* ---------------- * more & better checking is needed * ---------------- */ Assert(OidIsValid(indexRelation->rd_rel->relam)); /* XXX */ /* ---------------- * get the tuple descriptors from the relations so we know * how to form the index tuples.. * ---------------- */ heapDescriptor = RelationGetDescr(heapRelation); indexDescriptor = RelationGetDescr(indexRelation); /* ---------------- * datum and null are arrays in which we collect the index attributes * when forming a new index tuple. * ---------------- */ datum = (Datum *) palloc(numberOfAttributes * sizeof *datum); nullv = (char *) palloc(numberOfAttributes * sizeof *nullv); /* * If this is a predicate (partial) index, we will need to evaluate * the predicate using ExecQual, which requires the current tuple to * be in a slot of a TupleTable. In addition, ExecQual must have an * ExprContext referring to that slot. Here, we initialize dummy * TupleTable and ExprContext objects for this purpose. --Nels, Feb * '92 */ predicate = predInfo->pred; oldPred = predInfo->oldPred; #ifndef OMIT_PARTIAL_INDEX if (predicate != NULL || oldPred != NULL) { tupleTable = ExecCreateTupleTable(1); slot = ExecAllocTableSlot(tupleTable); econtext = makeNode(ExprContext); FillDummyExprContext(econtext, slot, heapDescriptor, InvalidBuffer); } else { econtext = NULL; tupleTable = 0; slot = NULL; } #endif /* OMIT_PARTIAL_INDEX */ /* ---------------- * Ok, begin our scan of the base relation. * ---------------- */ scan = heap_beginscan(heapRelation, /* relation */ 0, /* start at end */ SnapshotNow, /* seeself */ 0, /* number of keys */ (ScanKey) NULL); /* scan key */ reltuples = indtuples = 0; /* ---------------- * for each tuple in the base relation, we create an index * tuple and add it to the index relation. We keep a running * count of the number of tuples so that we can update pg_class * with correct statistics when we're done building the index. * ---------------- */ while (HeapTupleIsValid(heapTuple = heap_getnext(scan, 0))) { reltuples++; #ifndef OMIT_PARTIAL_INDEX /* * If oldPred != NULL, this is an EXTEND INDEX command, so skip * this tuple if it was already in the existing partial index */ if (oldPred != NULL) { /* SetSlotContents(slot, heapTuple); */ slot->val = heapTuple; if (ExecQual((List *) oldPred, econtext) == true) { indtuples++; continue; } } /* * Skip this tuple if it doesn't satisfy the partial-index * predicate */ if (predicate != NULL) { /* SetSlotContents(slot, heapTuple); */ slot->val = heapTuple; if (ExecQual((List *) predicate, econtext) == false) continue; } #endif /* OMIT_PARTIAL_INDEX */ indtuples++; /* ---------------- * FormIndexDatum fills in its datum and null parameters * with attribute information taken from the given heap tuple. * ---------------- */ FormIndexDatum(numberOfAttributes, /* num attributes */ attributeNumber, /* array of att nums to extract */ heapTuple, /* tuple from base relation */ heapDescriptor, /* heap tuple's descriptor */ datum, /* return: array of attributes */ nullv, /* return: array of char's */ funcInfo); indexTuple = index_formtuple(indexDescriptor, datum, nullv); indexTuple->t_tid = heapTuple->t_self; insertResult = index_insert(indexRelation, datum, nullv, &(heapTuple->t_self), heapRelation); if (insertResult) pfree(insertResult); pfree(indexTuple); } heap_endscan(scan); #ifndef OMIT_PARTIAL_INDEX if (predicate != NULL || oldPred != NULL) { /* parameter was 'false', almost certainly wrong --- tgl 9/21/99 */ ExecDestroyTupleTable(tupleTable, true); } #endif /* OMIT_PARTIAL_INDEX */ pfree(nullv); pfree(datum); /* * Since we just counted the tuples in the heap, we update its stats * in pg_class to guarantee that the planner takes advantage of the * index we just created. But, only update statistics during * normal index definitions, not for indices on system catalogs * created during bootstrap processing. We must close the relations * before updating statistics to guarantee that the relcache entries * are flushed when we increment the command counter in UpdateStats(). * But we do not release any locks on the relations; those will be * held until end of transaction. */ if (IsNormalProcessingMode()) { Oid hrelid = RelationGetRelid(heapRelation); Oid irelid = RelationGetRelid(indexRelation); heap_close(heapRelation, NoLock); index_close(indexRelation); UpdateStats(hrelid, reltuples, true); UpdateStats(irelid, indtuples, false); if (oldPred != NULL) { if (indtuples == reltuples) predicate = NULL; UpdateIndexPredicate(irelid, oldPred, predicate); } } } /* ---------------- * index_build * ---------------- */ void index_build(Relation heapRelation, Relation indexRelation, int numberOfAttributes, AttrNumber *attributeNumber, uint16 parameterCount, Datum *parameter, FuncIndexInfo *funcInfo, PredInfo *predInfo) { RegProcedure procedure; /* ---------------- * sanity checks * ---------------- */ Assert(RelationIsValid(indexRelation)); Assert(PointerIsValid(indexRelation->rd_am)); procedure = indexRelation->rd_am->ambuild; /* ---------------- * use the access method build procedure if supplied.. * ---------------- */ if (RegProcedureIsValid(procedure)) fmgr(procedure, heapRelation, indexRelation, numberOfAttributes, attributeNumber, RelationGetIndexStrategy(indexRelation), parameterCount, parameter, funcInfo, predInfo); else DefaultBuild(heapRelation, indexRelation, numberOfAttributes, attributeNumber, RelationGetIndexStrategy(indexRelation), parameterCount, parameter, funcInfo, predInfo); } /* * IndexIsUnique: given an index's relation OID, see if it * is unique using the system cache. */ bool IndexIsUnique(Oid indexId) { HeapTuple tuple; Form_pg_index index; tuple = SearchSysCacheTuple(INDEXRELID, ObjectIdGetDatum(indexId), 0, 0, 0); if (!HeapTupleIsValid(tuple)) { elog(ERROR, "IndexIsUnique: can't find index id %u", indexId); } index = (Form_pg_index) GETSTRUCT(tuple); Assert(index->indexrelid == indexId); return index->indisunique; } /* * IndexIsUniqueNoCache: same as above function, but don't use the * system cache. if we are called from btbuild, the transaction * that is adding the entry to pg_index has not been committed yet. * the system cache functions will do a heap scan, but only with * NowTimeQual, not SelfTimeQual, so it won't find tuples added * by the current transaction (which is good, because if the transaction * is aborted, you don't want the tuples sitting around in the cache). * so anyway, we have to do our own scan with SelfTimeQual. * this is only called when a new index is created, so it's OK * if it's slow. */ bool IndexIsUniqueNoCache(Oid indexId) { Relation pg_index; ScanKeyData skey[1]; HeapScanDesc scandesc; HeapTuple tuple; Form_pg_index index; bool isunique; pg_index = heap_openr(IndexRelationName, AccessShareLock); ScanKeyEntryInitialize(&skey[0], (bits16) 0x0, Anum_pg_index_indexrelid, (RegProcedure) F_OIDEQ, ObjectIdGetDatum(indexId)); scandesc = heap_beginscan(pg_index, 0, SnapshotSelf, 1, skey); /* NO CACHE */ tuple = heap_getnext(scandesc, 0); if (!HeapTupleIsValid(tuple)) elog(ERROR, "IndexIsUniqueNoCache: can't find index id %u", indexId); index = (Form_pg_index) GETSTRUCT(tuple); Assert(index->indexrelid == indexId); isunique = index->indisunique; heap_endscan(scandesc); heap_close(pg_index, AccessShareLock); return isunique; }