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1634 lines
44 KiB
C
1634 lines
44 KiB
C
/*
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* tablefunc
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*
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* Sample to demonstrate C functions which return setof scalar
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* and setof composite.
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* Joe Conway <mail@joeconway.com>
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* And contributors:
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* Nabil Sayegh <postgresql@e-trolley.de>
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*
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* Copyright (c) 2002-2006, PostgreSQL Global Development Group
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*
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* Permission to use, copy, modify, and distribute this software and its
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* documentation for any purpose, without fee, and without a written agreement
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* is hereby granted, provided that the above copyright notice and this
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* paragraph and the following two paragraphs appear in all copies.
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*
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* IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
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* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
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* LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
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* DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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* THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
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* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
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* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
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* ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
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* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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*
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*/
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#include "postgres.h"
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#include <math.h>
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#include "fmgr.h"
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#include "funcapi.h"
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#include "executor/spi.h"
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#include "lib/stringinfo.h"
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#include "miscadmin.h"
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#include "utils/builtins.h"
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#include "utils/guc.h"
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#include "utils/lsyscache.h"
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#include "tablefunc.h"
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PG_MODULE_MAGIC;
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static int load_categories_hash(char *cats_sql, MemoryContext per_query_ctx);
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static Tuplestorestate *get_crosstab_tuplestore(char *sql,
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int num_categories,
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TupleDesc tupdesc,
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MemoryContext per_query_ctx);
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static void validateConnectbyTupleDesc(TupleDesc tupdesc, bool show_branch, bool show_serial);
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static bool compatCrosstabTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2);
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static bool compatConnectbyTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2);
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static void get_normal_pair(float8 *x1, float8 *x2);
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static Tuplestorestate *connectby(char *relname,
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char *key_fld,
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char *parent_key_fld,
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char *orderby_fld,
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char *branch_delim,
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char *start_with,
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int max_depth,
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bool show_branch,
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bool show_serial,
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MemoryContext per_query_ctx,
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AttInMetadata *attinmeta);
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static Tuplestorestate *build_tuplestore_recursively(char *key_fld,
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char *parent_key_fld,
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char *relname,
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char *orderby_fld,
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char *branch_delim,
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char *start_with,
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char *branch,
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int level,
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int *serial,
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int max_depth,
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bool show_branch,
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bool show_serial,
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MemoryContext per_query_ctx,
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AttInMetadata *attinmeta,
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Tuplestorestate *tupstore);
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static char *quote_literal_cstr(char *rawstr);
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typedef struct
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{
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float8 mean; /* mean of the distribution */
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float8 stddev; /* stddev of the distribution */
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float8 carry_val; /* hold second generated value */
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bool use_carry; /* use second generated value */
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} normal_rand_fctx;
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typedef struct
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{
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SPITupleTable *spi_tuptable; /* sql results from user query */
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char *lastrowid; /* rowid of the last tuple sent */
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} crosstab_fctx;
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#define GET_TEXT(cstrp) DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(cstrp)))
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#define GET_STR(textp) DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(textp)))
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#define xpfree(var_) \
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do { \
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if (var_ != NULL) \
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{ \
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pfree(var_); \
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var_ = NULL; \
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} \
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} while (0)
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/* sign, 10 digits, '\0' */
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#define INT32_STRLEN 12
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/* hash table support */
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static HTAB *crosstab_HashTable;
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/* The information we cache about loaded procedures */
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typedef struct crosstab_cat_desc
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{
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char *catname;
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int attidx; /* zero based */
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} crosstab_cat_desc;
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#define MAX_CATNAME_LEN NAMEDATALEN
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#define INIT_CATS 64
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#define crosstab_HashTableLookup(CATNAME, CATDESC) \
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do { \
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crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN]; \
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\
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MemSet(key, 0, MAX_CATNAME_LEN); \
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snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATNAME); \
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hentry = (crosstab_HashEnt*) hash_search(crosstab_HashTable, \
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key, HASH_FIND, NULL); \
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if (hentry) \
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CATDESC = hentry->catdesc; \
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else \
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CATDESC = NULL; \
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} while(0)
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#define crosstab_HashTableInsert(CATDESC) \
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do { \
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crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN]; \
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\
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MemSet(key, 0, MAX_CATNAME_LEN); \
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snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATDESC->catname); \
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hentry = (crosstab_HashEnt*) hash_search(crosstab_HashTable, \
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key, HASH_ENTER, &found); \
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if (found) \
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ereport(ERROR, \
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(errcode(ERRCODE_DUPLICATE_OBJECT), \
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errmsg("duplicate category name"))); \
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hentry->catdesc = CATDESC; \
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} while(0)
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/* hash table */
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typedef struct crosstab_hashent
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{
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char internal_catname[MAX_CATNAME_LEN];
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crosstab_cat_desc *catdesc;
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} crosstab_HashEnt;
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/*
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* normal_rand - return requested number of random values
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* with a Gaussian (Normal) distribution.
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*
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* inputs are int numvals, float8 mean, and float8 stddev
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* returns setof float8
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*/
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PG_FUNCTION_INFO_V1(normal_rand);
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Datum
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normal_rand(PG_FUNCTION_ARGS)
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{
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FuncCallContext *funcctx;
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int call_cntr;
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int max_calls;
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normal_rand_fctx *fctx;
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float8 mean;
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float8 stddev;
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float8 carry_val;
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bool use_carry;
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MemoryContext oldcontext;
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/* stuff done only on the first call of the function */
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if (SRF_IS_FIRSTCALL())
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{
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/* create a function context for cross-call persistence */
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funcctx = SRF_FIRSTCALL_INIT();
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/*
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* switch to memory context appropriate for multiple function calls
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*/
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oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
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/* total number of tuples to be returned */
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funcctx->max_calls = PG_GETARG_UINT32(0);
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/* allocate memory for user context */
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fctx = (normal_rand_fctx *) palloc(sizeof(normal_rand_fctx));
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/*
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* Use fctx to keep track of upper and lower bounds from call to call.
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* It will also be used to carry over the spare value we get from the
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* Box-Muller algorithm so that we only actually calculate a new value
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* every other call.
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*/
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fctx->mean = PG_GETARG_FLOAT8(1);
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fctx->stddev = PG_GETARG_FLOAT8(2);
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fctx->carry_val = 0;
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fctx->use_carry = false;
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funcctx->user_fctx = fctx;
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MemoryContextSwitchTo(oldcontext);
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}
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/* stuff done on every call of the function */
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funcctx = SRF_PERCALL_SETUP();
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call_cntr = funcctx->call_cntr;
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max_calls = funcctx->max_calls;
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fctx = funcctx->user_fctx;
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mean = fctx->mean;
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stddev = fctx->stddev;
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carry_val = fctx->carry_val;
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use_carry = fctx->use_carry;
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if (call_cntr < max_calls) /* do when there is more left to send */
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{
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float8 result;
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if (use_carry)
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{
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/*
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* reset use_carry and use second value obtained on last pass
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*/
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fctx->use_carry = false;
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result = carry_val;
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}
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else
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{
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float8 normval_1;
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float8 normval_2;
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/* Get the next two normal values */
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get_normal_pair(&normval_1, &normval_2);
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/* use the first */
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result = mean + (stddev * normval_1);
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/* and save the second */
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fctx->carry_val = mean + (stddev * normval_2);
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fctx->use_carry = true;
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}
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/* send the result */
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SRF_RETURN_NEXT(funcctx, Float8GetDatum(result));
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}
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else
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/* do when there is no more left */
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SRF_RETURN_DONE(funcctx);
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}
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/*
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* get_normal_pair()
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* Assigns normally distributed (Gaussian) values to a pair of provided
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* parameters, with mean 0, standard deviation 1.
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*
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* This routine implements Algorithm P (Polar method for normal deviates)
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* from Knuth's _The_Art_of_Computer_Programming_, Volume 2, 3rd ed., pages
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* 122-126. Knuth cites his source as "The polar method", G. E. P. Box, M. E.
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* Muller, and G. Marsaglia, _Annals_Math,_Stat._ 29 (1958), 610-611.
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*
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*/
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static void
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get_normal_pair(float8 *x1, float8 *x2)
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{
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float8 u1,
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u2,
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v1,
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v2,
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s;
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do
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{
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u1 = (float8) random() / (float8) MAX_RANDOM_VALUE;
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u2 = (float8) random() / (float8) MAX_RANDOM_VALUE;
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v1 = (2.0 * u1) - 1.0;
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v2 = (2.0 * u2) - 1.0;
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s = v1 * v1 + v2 * v2;
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} while (s >= 1.0);
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if (s == 0)
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{
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*x1 = 0;
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*x2 = 0;
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}
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else
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{
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s = sqrt((-2.0 * log(s)) / s);
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*x1 = v1 * s;
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*x2 = v2 * s;
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}
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}
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/*
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* crosstab - create a crosstab of rowids and values columns from a
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* SQL statement returning one rowid column, one category column,
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* and one value column.
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*
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* e.g. given sql which produces:
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*
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* rowid cat value
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* ------+-------+-------
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* row1 cat1 val1
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* row1 cat2 val2
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* row1 cat3 val3
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* row1 cat4 val4
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* row2 cat1 val5
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* row2 cat2 val6
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* row2 cat3 val7
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* row2 cat4 val8
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*
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* crosstab returns:
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* <===== values columns =====>
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* rowid cat1 cat2 cat3 cat4
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* ------+-------+-------+-------+-------
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* row1 val1 val2 val3 val4
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* row2 val5 val6 val7 val8
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*
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* NOTES:
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* 1. SQL result must be ordered by 1,2.
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* 2. The number of values columns depends on the tuple description
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* of the function's declared return type. The return type's columns
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* must match the datatypes of the SQL query's result. The datatype
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* of the category column can be anything, however.
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* 3. Missing values (i.e. not enough adjacent rows of same rowid to
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* fill the number of result values columns) are filled in with nulls.
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* 4. Extra values (i.e. too many adjacent rows of same rowid to fill
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* the number of result values columns) are skipped.
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* 5. Rows with all nulls in the values columns are skipped.
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*/
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PG_FUNCTION_INFO_V1(crosstab);
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Datum
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crosstab(PG_FUNCTION_ARGS)
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{
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FuncCallContext *funcctx;
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TupleDesc ret_tupdesc;
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int call_cntr;
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int max_calls;
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AttInMetadata *attinmeta;
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SPITupleTable *spi_tuptable = NULL;
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TupleDesc spi_tupdesc;
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char *lastrowid = NULL;
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crosstab_fctx *fctx;
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int i;
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int num_categories;
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MemoryContext oldcontext;
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/* stuff done only on the first call of the function */
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if (SRF_IS_FIRSTCALL())
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{
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char *sql = GET_STR(PG_GETARG_TEXT_P(0));
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TupleDesc tupdesc;
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int ret;
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int proc;
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/* create a function context for cross-call persistence */
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funcctx = SRF_FIRSTCALL_INIT();
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/*
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* switch to memory context appropriate for multiple function calls
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*/
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oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
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/* Connect to SPI manager */
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if ((ret = SPI_connect()) < 0)
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/* internal error */
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elog(ERROR, "crosstab: SPI_connect returned %d", ret);
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/* Retrieve the desired rows */
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ret = SPI_execute(sql, true, 0);
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proc = SPI_processed;
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/* Check for qualifying tuples */
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if ((ret == SPI_OK_SELECT) && (proc > 0))
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{
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spi_tuptable = SPI_tuptable;
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spi_tupdesc = spi_tuptable->tupdesc;
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/*----------
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* The provided SQL query must always return three columns.
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*
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* 1. rowname
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* the label or identifier for each row in the final result
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* 2. category
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* the label or identifier for each column in the final result
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* 3. values
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* the value for each column in the final result
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*----------
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*/
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if (spi_tupdesc->natts != 3)
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ereport(ERROR,
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(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
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errmsg("invalid source data SQL statement"),
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errdetail("The provided SQL must return 3 "
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"columns: rowid, category, and values.")));
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}
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else
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{
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/* no qualifying tuples */
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SPI_finish();
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SRF_RETURN_DONE(funcctx);
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}
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/* SPI switches context on us, so reset it */
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MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
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/* get a tuple descriptor for our result type */
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switch (get_call_result_type(fcinfo, NULL, &tupdesc))
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{
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case TYPEFUNC_COMPOSITE:
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/* success */
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break;
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case TYPEFUNC_RECORD:
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/* failed to determine actual type of RECORD */
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("function returning record called in context "
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"that cannot accept type record")));
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break;
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default:
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/* result type isn't composite */
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elog(ERROR, "return type must be a row type");
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break;
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}
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/* make sure we have a persistent copy of the tupdesc */
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tupdesc = CreateTupleDescCopy(tupdesc);
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/*
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* Check that return tupdesc is compatible with the data we got from
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* SPI, at least based on number and type of attributes
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*/
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if (!compatCrosstabTupleDescs(tupdesc, spi_tupdesc))
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ereport(ERROR,
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(errcode(ERRCODE_SYNTAX_ERROR),
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errmsg("return and sql tuple descriptions are " \
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"incompatible")));
|
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/*
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* Generate attribute metadata needed later to produce tuples from raw
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* C strings
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*/
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attinmeta = TupleDescGetAttInMetadata(tupdesc);
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funcctx->attinmeta = attinmeta;
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|
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/* allocate memory for user context */
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fctx = (crosstab_fctx *) palloc(sizeof(crosstab_fctx));
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|
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/*
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* Save spi data for use across calls
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*/
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fctx->spi_tuptable = spi_tuptable;
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fctx->lastrowid = NULL;
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funcctx->user_fctx = fctx;
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/* total number of tuples to be returned */
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funcctx->max_calls = proc;
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MemoryContextSwitchTo(oldcontext);
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}
|
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|
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/* stuff done on every call of the function */
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funcctx = SRF_PERCALL_SETUP();
|
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|
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/*
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* initialize per-call variables
|
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*/
|
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call_cntr = funcctx->call_cntr;
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max_calls = funcctx->max_calls;
|
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|
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/* user context info */
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fctx = (crosstab_fctx *) funcctx->user_fctx;
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lastrowid = fctx->lastrowid;
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spi_tuptable = fctx->spi_tuptable;
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/* the sql tuple */
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spi_tupdesc = spi_tuptable->tupdesc;
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/* attribute return type and return tuple description */
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attinmeta = funcctx->attinmeta;
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ret_tupdesc = attinmeta->tupdesc;
|
|
|
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/* the return tuple always must have 1 rowid + num_categories columns */
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num_categories = ret_tupdesc->natts - 1;
|
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|
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if (call_cntr < max_calls) /* do when there is more left to send */
|
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{
|
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HeapTuple tuple;
|
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Datum result;
|
|
char **values;
|
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bool allnulls = true;
|
|
|
|
while (true)
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{
|
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/* allocate space */
|
|
values = (char **) palloc((1 + num_categories) * sizeof(char *));
|
|
|
|
/* and make sure it's clear */
|
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memset(values, '\0', (1 + num_categories) * sizeof(char *));
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|
|
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/*
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* now loop through the sql results and assign each value in
|
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* sequence to the next category
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|
*/
|
|
for (i = 0; i < num_categories; i++)
|
|
{
|
|
HeapTuple spi_tuple;
|
|
char *rowid = NULL;
|
|
|
|
/* see if we've gone too far already */
|
|
if (call_cntr >= max_calls)
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|
break;
|
|
|
|
/* get the next sql result tuple */
|
|
spi_tuple = spi_tuptable->vals[call_cntr];
|
|
|
|
/* get the rowid from the current sql result tuple */
|
|
rowid = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
|
|
|
|
/*
|
|
* If this is the first pass through the values for this rowid
|
|
* set it, otherwise make sure it hasn't changed on us. Also
|
|
* check to see if the rowid is the same as that of the last
|
|
* tuple sent -- if so, skip this tuple entirely
|
|
*/
|
|
if (i == 0)
|
|
values[0] = pstrdup(rowid);
|
|
|
|
if ((rowid != NULL) && (strcmp(rowid, values[0]) == 0))
|
|
{
|
|
if ((lastrowid != NULL) && (strcmp(rowid, lastrowid) == 0))
|
|
break;
|
|
else if (allnulls == true)
|
|
allnulls = false;
|
|
|
|
/*
|
|
* Get the next category item value, which is alway
|
|
* attribute number three.
|
|
*
|
|
* Be careful to sssign the value to the array index based
|
|
* on which category we are presently processing.
|
|
*/
|
|
values[1 + i] = SPI_getvalue(spi_tuple, spi_tupdesc, 3);
|
|
|
|
/*
|
|
* increment the counter since we consume a row for each
|
|
* category, but not for last pass because the API will do
|
|
* that for us
|
|
*/
|
|
if (i < (num_categories - 1))
|
|
call_cntr = ++funcctx->call_cntr;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* We'll fill in NULLs for the missing values, but we need
|
|
* to decrement the counter since this sql result row
|
|
* doesn't belong to the current output tuple.
|
|
*/
|
|
call_cntr = --funcctx->call_cntr;
|
|
break;
|
|
}
|
|
|
|
if (rowid != NULL)
|
|
xpfree(rowid);
|
|
}
|
|
|
|
xpfree(fctx->lastrowid);
|
|
|
|
if (values[0] != NULL)
|
|
{
|
|
/*
|
|
* switch to memory context appropriate for multiple function
|
|
* calls
|
|
*/
|
|
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
|
|
|
|
lastrowid = fctx->lastrowid = pstrdup(values[0]);
|
|
MemoryContextSwitchTo(oldcontext);
|
|
}
|
|
|
|
if (!allnulls)
|
|
{
|
|
/* build the tuple */
|
|
tuple = BuildTupleFromCStrings(attinmeta, values);
|
|
|
|
/* make the tuple into a datum */
|
|
result = HeapTupleGetDatum(tuple);
|
|
|
|
/* Clean up */
|
|
for (i = 0; i < num_categories + 1; i++)
|
|
if (values[i] != NULL)
|
|
xpfree(values[i]);
|
|
xpfree(values);
|
|
|
|
SRF_RETURN_NEXT(funcctx, result);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* Skipping this tuple entirely, but we need to advance the
|
|
* counter like the API would if we had returned one.
|
|
*/
|
|
call_cntr = ++funcctx->call_cntr;
|
|
|
|
/* we'll start over at the top */
|
|
xpfree(values);
|
|
|
|
/* see if we've gone too far already */
|
|
if (call_cntr >= max_calls)
|
|
{
|
|
/* release SPI related resources */
|
|
SPI_finish();
|
|
SRF_RETURN_DONE(funcctx);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else
|
|
/* do when there is no more left */
|
|
{
|
|
/* release SPI related resources */
|
|
SPI_finish();
|
|
SRF_RETURN_DONE(funcctx);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* crosstab_hash - reimplement crosstab as materialized function and
|
|
* properly deal with missing values (i.e. don't pack remaining
|
|
* values to the left)
|
|
*
|
|
* crosstab - create a crosstab of rowids and values columns from a
|
|
* SQL statement returning one rowid column, one category column,
|
|
* and one value column.
|
|
*
|
|
* e.g. given sql which produces:
|
|
*
|
|
* rowid cat value
|
|
* ------+-------+-------
|
|
* row1 cat1 val1
|
|
* row1 cat2 val2
|
|
* row1 cat4 val4
|
|
* row2 cat1 val5
|
|
* row2 cat2 val6
|
|
* row2 cat3 val7
|
|
* row2 cat4 val8
|
|
*
|
|
* crosstab returns:
|
|
* <===== values columns =====>
|
|
* rowid cat1 cat2 cat3 cat4
|
|
* ------+-------+-------+-------+-------
|
|
* row1 val1 val2 null val4
|
|
* row2 val5 val6 val7 val8
|
|
*
|
|
* NOTES:
|
|
* 1. SQL result must be ordered by 1.
|
|
* 2. The number of values columns depends on the tuple description
|
|
* of the function's declared return type.
|
|
* 3. Missing values (i.e. missing category) are filled in with nulls.
|
|
* 4. Extra values (i.e. not in category results) are skipped.
|
|
*/
|
|
PG_FUNCTION_INFO_V1(crosstab_hash);
|
|
Datum
|
|
crosstab_hash(PG_FUNCTION_ARGS)
|
|
{
|
|
char *sql = GET_STR(PG_GETARG_TEXT_P(0));
|
|
char *cats_sql = GET_STR(PG_GETARG_TEXT_P(1));
|
|
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
|
|
TupleDesc tupdesc;
|
|
MemoryContext per_query_ctx;
|
|
MemoryContext oldcontext;
|
|
int num_categories;
|
|
|
|
/* check to see if caller supports us returning a tuplestore */
|
|
if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("set-valued function called in context that cannot accept a set")));
|
|
if (!(rsinfo->allowedModes & SFRM_Materialize))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialize mode required, but it is not " \
|
|
"allowed in this context")));
|
|
|
|
per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* get the requested return tuple description */
|
|
tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
|
|
|
|
/*
|
|
* Check to make sure we have a reasonable tuple descriptor
|
|
*
|
|
* Note we will attempt to coerce the values into whatever the return
|
|
* attribute type is and depend on the "in" function to complain if
|
|
* needed.
|
|
*/
|
|
if (tupdesc->natts < 2)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("query-specified return tuple and " \
|
|
"crosstab function are not compatible")));
|
|
|
|
/* load up the categories hash table */
|
|
num_categories = load_categories_hash(cats_sql, per_query_ctx);
|
|
|
|
/* let the caller know we're sending back a tuplestore */
|
|
rsinfo->returnMode = SFRM_Materialize;
|
|
|
|
/* now go build it */
|
|
rsinfo->setResult = get_crosstab_tuplestore(sql,
|
|
num_categories,
|
|
tupdesc,
|
|
per_query_ctx);
|
|
|
|
/*
|
|
* SFRM_Materialize mode expects us to return a NULL Datum. The actual
|
|
* tuples are in our tuplestore and passed back through rsinfo->setResult.
|
|
* rsinfo->setDesc is set to the tuple description that we actually used
|
|
* to build our tuples with, so the caller can verify we did what it was
|
|
* expecting.
|
|
*/
|
|
rsinfo->setDesc = tupdesc;
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
return (Datum) 0;
|
|
}
|
|
|
|
/*
|
|
* load up the categories hash table
|
|
*/
|
|
static int
|
|
load_categories_hash(char *cats_sql, MemoryContext per_query_ctx)
|
|
{
|
|
HASHCTL ctl;
|
|
int ret;
|
|
int proc;
|
|
MemoryContext SPIcontext;
|
|
int num_categories = 0;
|
|
|
|
/* initialize the category hash table */
|
|
ctl.keysize = MAX_CATNAME_LEN;
|
|
ctl.entrysize = sizeof(crosstab_HashEnt);
|
|
|
|
/*
|
|
* use INIT_CATS, defined above as a guess of how many hash table entries
|
|
* to create, initially
|
|
*/
|
|
crosstab_HashTable = hash_create("crosstab hash", INIT_CATS, &ctl, HASH_ELEM);
|
|
|
|
/* Connect to SPI manager */
|
|
if ((ret = SPI_connect()) < 0)
|
|
/* internal error */
|
|
elog(ERROR, "load_categories_hash: SPI_connect returned %d", ret);
|
|
|
|
/* Retrieve the category name rows */
|
|
ret = SPI_execute(cats_sql, true, 0);
|
|
num_categories = proc = SPI_processed;
|
|
|
|
/* Check for qualifying tuples */
|
|
if ((ret == SPI_OK_SELECT) && (proc > 0))
|
|
{
|
|
SPITupleTable *spi_tuptable = SPI_tuptable;
|
|
TupleDesc spi_tupdesc = spi_tuptable->tupdesc;
|
|
int i;
|
|
|
|
/*
|
|
* The provided categories SQL query must always return one column:
|
|
* category - the label or identifier for each column
|
|
*/
|
|
if (spi_tupdesc->natts != 1)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("provided \"categories\" SQL must " \
|
|
"return 1 column of at least one row")));
|
|
|
|
for (i = 0; i < proc; i++)
|
|
{
|
|
crosstab_cat_desc *catdesc;
|
|
char *catname;
|
|
HeapTuple spi_tuple;
|
|
|
|
/* get the next sql result tuple */
|
|
spi_tuple = spi_tuptable->vals[i];
|
|
|
|
/* get the category from the current sql result tuple */
|
|
catname = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
|
|
|
|
SPIcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
catdesc = (crosstab_cat_desc *) palloc(sizeof(crosstab_cat_desc));
|
|
catdesc->catname = catname;
|
|
catdesc->attidx = i;
|
|
|
|
/* Add the proc description block to the hashtable */
|
|
crosstab_HashTableInsert(catdesc);
|
|
|
|
MemoryContextSwitchTo(SPIcontext);
|
|
}
|
|
}
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
/* internal error */
|
|
elog(ERROR, "load_categories_hash: SPI_finish() failed");
|
|
|
|
return num_categories;
|
|
}
|
|
|
|
/*
|
|
* create and populate the crosstab tuplestore using the provided source query
|
|
*/
|
|
static Tuplestorestate *
|
|
get_crosstab_tuplestore(char *sql,
|
|
int num_categories,
|
|
TupleDesc tupdesc,
|
|
MemoryContext per_query_ctx)
|
|
{
|
|
Tuplestorestate *tupstore;
|
|
AttInMetadata *attinmeta = TupleDescGetAttInMetadata(tupdesc);
|
|
char **values;
|
|
HeapTuple tuple;
|
|
int ret;
|
|
int proc;
|
|
MemoryContext SPIcontext;
|
|
|
|
/* initialize our tuplestore */
|
|
tupstore = tuplestore_begin_heap(true, false, work_mem);
|
|
|
|
/* Connect to SPI manager */
|
|
if ((ret = SPI_connect()) < 0)
|
|
/* internal error */
|
|
elog(ERROR, "get_crosstab_tuplestore: SPI_connect returned %d", ret);
|
|
|
|
/* Now retrieve the crosstab source rows */
|
|
ret = SPI_execute(sql, true, 0);
|
|
proc = SPI_processed;
|
|
|
|
/* Check for qualifying tuples */
|
|
if ((ret == SPI_OK_SELECT) && (proc > 0))
|
|
{
|
|
SPITupleTable *spi_tuptable = SPI_tuptable;
|
|
TupleDesc spi_tupdesc = spi_tuptable->tupdesc;
|
|
int ncols = spi_tupdesc->natts;
|
|
char *rowid;
|
|
char *lastrowid = NULL;
|
|
int i,
|
|
j;
|
|
int result_ncols;
|
|
|
|
if (num_categories == 0)
|
|
{
|
|
/* no qualifying category tuples */
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("provided \"categories\" SQL must " \
|
|
"return 1 column of at least one row")));
|
|
}
|
|
|
|
/*
|
|
* The provided SQL query must always return at least three columns:
|
|
*
|
|
* 1. rowname the label for each row - column 1 in the final result
|
|
* 2. category the label for each value-column in the final result 3.
|
|
* value the values used to populate the value-columns
|
|
*
|
|
* If there are more than three columns, the last two are taken as
|
|
* "category" and "values". The first column is taken as "rowname".
|
|
* Additional columns (2 thru N-2) are assumed the same for the same
|
|
* "rowname", and are copied into the result tuple from the first time
|
|
* we encounter a particular rowname.
|
|
*/
|
|
if (ncols < 3)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
|
|
errmsg("invalid source data SQL statement"),
|
|
errdetail("The provided SQL must return 3 " \
|
|
" columns; rowid, category, and values.")));
|
|
|
|
result_ncols = (ncols - 2) + num_categories;
|
|
|
|
/* Recheck to make sure we tuple descriptor still looks reasonable */
|
|
if (tupdesc->natts != result_ncols)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("Query-specified return " \
|
|
"tuple has %d columns but crosstab " \
|
|
"returns %d.", tupdesc->natts, result_ncols)));
|
|
|
|
/* allocate space */
|
|
values = (char **) palloc(result_ncols * sizeof(char *));
|
|
|
|
/* and make sure it's clear */
|
|
memset(values, '\0', result_ncols * sizeof(char *));
|
|
|
|
for (i = 0; i < proc; i++)
|
|
{
|
|
HeapTuple spi_tuple;
|
|
crosstab_cat_desc *catdesc;
|
|
char *catname;
|
|
|
|
/* get the next sql result tuple */
|
|
spi_tuple = spi_tuptable->vals[i];
|
|
|
|
/* get the rowid from the current sql result tuple */
|
|
rowid = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
|
|
|
|
/* if rowid is null, skip this tuple entirely */
|
|
if (rowid == NULL)
|
|
continue;
|
|
|
|
/*
|
|
* if we're on a new output row, grab the column values up to
|
|
* column N-2 now
|
|
*/
|
|
if ((lastrowid == NULL) || (strcmp(rowid, lastrowid) != 0))
|
|
{
|
|
/*
|
|
* a new row means we need to flush the old one first, unless
|
|
* we're on the very first row
|
|
*/
|
|
if (lastrowid != NULL)
|
|
{
|
|
/*
|
|
* switch to appropriate context while storing the tuple
|
|
*/
|
|
SPIcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* rowid changed, flush the previous output row */
|
|
tuple = BuildTupleFromCStrings(attinmeta, values);
|
|
tuplestore_puttuple(tupstore, tuple);
|
|
for (j = 0; j < result_ncols; j++)
|
|
xpfree(values[j]);
|
|
|
|
/* now reset the context */
|
|
MemoryContextSwitchTo(SPIcontext);
|
|
}
|
|
|
|
values[0] = rowid;
|
|
for (j = 1; j < ncols - 2; j++)
|
|
values[j] = SPI_getvalue(spi_tuple, spi_tupdesc, j + 1);
|
|
}
|
|
|
|
/* look up the category and fill in the appropriate column */
|
|
catname = SPI_getvalue(spi_tuple, spi_tupdesc, ncols - 1);
|
|
|
|
if (catname != NULL)
|
|
{
|
|
crosstab_HashTableLookup(catname, catdesc);
|
|
|
|
if (catdesc)
|
|
values[catdesc->attidx + ncols - 2] =
|
|
SPI_getvalue(spi_tuple, spi_tupdesc, ncols);
|
|
}
|
|
|
|
xpfree(lastrowid);
|
|
lastrowid = pstrdup(rowid);
|
|
}
|
|
|
|
/* switch to appropriate context while storing the tuple */
|
|
SPIcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* flush the last output row */
|
|
tuple = BuildTupleFromCStrings(attinmeta, values);
|
|
tuplestore_puttuple(tupstore, tuple);
|
|
|
|
/* now reset the context */
|
|
MemoryContextSwitchTo(SPIcontext);
|
|
|
|
}
|
|
|
|
if (SPI_finish() != SPI_OK_FINISH)
|
|
/* internal error */
|
|
elog(ERROR, "get_crosstab_tuplestore: SPI_finish() failed");
|
|
|
|
tuplestore_donestoring(tupstore);
|
|
|
|
return tupstore;
|
|
}
|
|
|
|
/*
|
|
* connectby_text - produce a result set from a hierarchical (parent/child)
|
|
* table.
|
|
*
|
|
* e.g. given table foo:
|
|
*
|
|
* keyid parent_keyid pos
|
|
* ------+------------+--
|
|
* row1 NULL 0
|
|
* row2 row1 0
|
|
* row3 row1 0
|
|
* row4 row2 1
|
|
* row5 row2 0
|
|
* row6 row4 0
|
|
* row7 row3 0
|
|
* row8 row6 0
|
|
* row9 row5 0
|
|
*
|
|
*
|
|
* connectby(text relname, text keyid_fld, text parent_keyid_fld
|
|
* [, text orderby_fld], text start_with, int max_depth
|
|
* [, text branch_delim])
|
|
* connectby('foo', 'keyid', 'parent_keyid', 'pos', 'row2', 0, '~') returns:
|
|
*
|
|
* keyid parent_id level branch serial
|
|
* ------+-----------+--------+-----------------------
|
|
* row2 NULL 0 row2 1
|
|
* row5 row2 1 row2~row5 2
|
|
* row9 row5 2 row2~row5~row9 3
|
|
* row4 row2 1 row2~row4 4
|
|
* row6 row4 2 row2~row4~row6 5
|
|
* row8 row6 3 row2~row4~row6~row8 6
|
|
*
|
|
*/
|
|
PG_FUNCTION_INFO_V1(connectby_text);
|
|
|
|
#define CONNECTBY_NCOLS 4
|
|
#define CONNECTBY_NCOLS_NOBRANCH 3
|
|
|
|
Datum
|
|
connectby_text(PG_FUNCTION_ARGS)
|
|
{
|
|
char *relname = GET_STR(PG_GETARG_TEXT_P(0));
|
|
char *key_fld = GET_STR(PG_GETARG_TEXT_P(1));
|
|
char *parent_key_fld = GET_STR(PG_GETARG_TEXT_P(2));
|
|
char *start_with = GET_STR(PG_GETARG_TEXT_P(3));
|
|
int max_depth = PG_GETARG_INT32(4);
|
|
char *branch_delim = NULL;
|
|
bool show_branch = false;
|
|
bool show_serial = false;
|
|
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
|
|
TupleDesc tupdesc;
|
|
AttInMetadata *attinmeta;
|
|
MemoryContext per_query_ctx;
|
|
MemoryContext oldcontext;
|
|
|
|
/* check to see if caller supports us returning a tuplestore */
|
|
if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("set-valued function called in context that cannot accept a set")));
|
|
if (!(rsinfo->allowedModes & SFRM_Materialize))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialize mode required, but it is not " \
|
|
"allowed in this context")));
|
|
|
|
if (fcinfo->nargs == 6)
|
|
{
|
|
branch_delim = GET_STR(PG_GETARG_TEXT_P(5));
|
|
show_branch = true;
|
|
}
|
|
else
|
|
/* default is no show, tilde for the delimiter */
|
|
branch_delim = pstrdup("~");
|
|
|
|
per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* get the requested return tuple description */
|
|
tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
|
|
|
|
/* does it meet our needs */
|
|
validateConnectbyTupleDesc(tupdesc, show_branch, show_serial);
|
|
|
|
/* OK, use it then */
|
|
attinmeta = TupleDescGetAttInMetadata(tupdesc);
|
|
|
|
/* OK, go to work */
|
|
rsinfo->returnMode = SFRM_Materialize;
|
|
rsinfo->setResult = connectby(relname,
|
|
key_fld,
|
|
parent_key_fld,
|
|
NULL,
|
|
branch_delim,
|
|
start_with,
|
|
max_depth,
|
|
show_branch,
|
|
show_serial,
|
|
per_query_ctx,
|
|
attinmeta);
|
|
rsinfo->setDesc = tupdesc;
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/*
|
|
* SFRM_Materialize mode expects us to return a NULL Datum. The actual
|
|
* tuples are in our tuplestore and passed back through rsinfo->setResult.
|
|
* rsinfo->setDesc is set to the tuple description that we actually used
|
|
* to build our tuples with, so the caller can verify we did what it was
|
|
* expecting.
|
|
*/
|
|
return (Datum) 0;
|
|
}
|
|
|
|
PG_FUNCTION_INFO_V1(connectby_text_serial);
|
|
Datum
|
|
connectby_text_serial(PG_FUNCTION_ARGS)
|
|
{
|
|
char *relname = GET_STR(PG_GETARG_TEXT_P(0));
|
|
char *key_fld = GET_STR(PG_GETARG_TEXT_P(1));
|
|
char *parent_key_fld = GET_STR(PG_GETARG_TEXT_P(2));
|
|
char *orderby_fld = GET_STR(PG_GETARG_TEXT_P(3));
|
|
char *start_with = GET_STR(PG_GETARG_TEXT_P(4));
|
|
int max_depth = PG_GETARG_INT32(5);
|
|
char *branch_delim = NULL;
|
|
bool show_branch = false;
|
|
bool show_serial = true;
|
|
|
|
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
|
|
TupleDesc tupdesc;
|
|
AttInMetadata *attinmeta;
|
|
MemoryContext per_query_ctx;
|
|
MemoryContext oldcontext;
|
|
|
|
/* check to see if caller supports us returning a tuplestore */
|
|
if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("set-valued function called in context that cannot accept a set")));
|
|
if (!(rsinfo->allowedModes & SFRM_Materialize))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("materialize mode required, but it is not " \
|
|
"allowed in this context")));
|
|
|
|
if (fcinfo->nargs == 7)
|
|
{
|
|
branch_delim = GET_STR(PG_GETARG_TEXT_P(6));
|
|
show_branch = true;
|
|
}
|
|
else
|
|
/* default is no show, tilde for the delimiter */
|
|
branch_delim = pstrdup("~");
|
|
|
|
per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* get the requested return tuple description */
|
|
tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
|
|
|
|
/* does it meet our needs */
|
|
validateConnectbyTupleDesc(tupdesc, show_branch, show_serial);
|
|
|
|
/* OK, use it then */
|
|
attinmeta = TupleDescGetAttInMetadata(tupdesc);
|
|
|
|
/* OK, go to work */
|
|
rsinfo->returnMode = SFRM_Materialize;
|
|
rsinfo->setResult = connectby(relname,
|
|
key_fld,
|
|
parent_key_fld,
|
|
orderby_fld,
|
|
branch_delim,
|
|
start_with,
|
|
max_depth,
|
|
show_branch,
|
|
show_serial,
|
|
per_query_ctx,
|
|
attinmeta);
|
|
rsinfo->setDesc = tupdesc;
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/*
|
|
* SFRM_Materialize mode expects us to return a NULL Datum. The actual
|
|
* tuples are in our tuplestore and passed back through rsinfo->setResult.
|
|
* rsinfo->setDesc is set to the tuple description that we actually used
|
|
* to build our tuples with, so the caller can verify we did what it was
|
|
* expecting.
|
|
*/
|
|
return (Datum) 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* connectby - does the real work for connectby_text()
|
|
*/
|
|
static Tuplestorestate *
|
|
connectby(char *relname,
|
|
char *key_fld,
|
|
char *parent_key_fld,
|
|
char *orderby_fld,
|
|
char *branch_delim,
|
|
char *start_with,
|
|
int max_depth,
|
|
bool show_branch,
|
|
bool show_serial,
|
|
MemoryContext per_query_ctx,
|
|
AttInMetadata *attinmeta)
|
|
{
|
|
Tuplestorestate *tupstore = NULL;
|
|
int ret;
|
|
MemoryContext oldcontext;
|
|
|
|
int serial = 1;
|
|
|
|
/* Connect to SPI manager */
|
|
if ((ret = SPI_connect()) < 0)
|
|
/* internal error */
|
|
elog(ERROR, "connectby: SPI_connect returned %d", ret);
|
|
|
|
/* switch to longer term context to create the tuple store */
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* initialize our tuplestore */
|
|
tupstore = tuplestore_begin_heap(true, false, work_mem);
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/* now go get the whole tree */
|
|
tupstore = build_tuplestore_recursively(key_fld,
|
|
parent_key_fld,
|
|
relname,
|
|
orderby_fld,
|
|
branch_delim,
|
|
start_with,
|
|
start_with, /* current_branch */
|
|
0, /* initial level is 0 */
|
|
&serial, /* initial serial is 1 */
|
|
max_depth,
|
|
show_branch,
|
|
show_serial,
|
|
per_query_ctx,
|
|
attinmeta,
|
|
tupstore);
|
|
|
|
SPI_finish();
|
|
|
|
return tupstore;
|
|
}
|
|
|
|
static Tuplestorestate *
|
|
build_tuplestore_recursively(char *key_fld,
|
|
char *parent_key_fld,
|
|
char *relname,
|
|
char *orderby_fld,
|
|
char *branch_delim,
|
|
char *start_with,
|
|
char *branch,
|
|
int level,
|
|
int *serial,
|
|
int max_depth,
|
|
bool show_branch,
|
|
bool show_serial,
|
|
MemoryContext per_query_ctx,
|
|
AttInMetadata *attinmeta,
|
|
Tuplestorestate *tupstore)
|
|
{
|
|
TupleDesc tupdesc = attinmeta->tupdesc;
|
|
MemoryContext oldcontext;
|
|
int ret;
|
|
int proc;
|
|
int serial_column;
|
|
StringInfoData sql;
|
|
char **values;
|
|
char *current_key;
|
|
char *current_key_parent;
|
|
char current_level[INT32_STRLEN];
|
|
char serial_str[INT32_STRLEN];
|
|
char *current_branch;
|
|
HeapTuple tuple;
|
|
|
|
if (max_depth > 0 && level > max_depth)
|
|
return tupstore;
|
|
|
|
initStringInfo(&sql);
|
|
|
|
/* Build initial sql statement */
|
|
if (!show_serial)
|
|
{
|
|
appendStringInfo(&sql, "SELECT %s, %s FROM %s WHERE %s = %s AND %s IS NOT NULL AND %s <> %s",
|
|
key_fld,
|
|
parent_key_fld,
|
|
relname,
|
|
parent_key_fld,
|
|
quote_literal_cstr(start_with),
|
|
key_fld, key_fld, parent_key_fld);
|
|
serial_column = 0;
|
|
}
|
|
else
|
|
{
|
|
appendStringInfo(&sql, "SELECT %s, %s FROM %s WHERE %s = %s AND %s IS NOT NULL AND %s <> %s ORDER BY %s",
|
|
key_fld,
|
|
parent_key_fld,
|
|
relname,
|
|
parent_key_fld,
|
|
quote_literal_cstr(start_with),
|
|
key_fld, key_fld, parent_key_fld,
|
|
orderby_fld);
|
|
serial_column = 1;
|
|
}
|
|
|
|
if (show_branch)
|
|
values = (char **) palloc((CONNECTBY_NCOLS + serial_column) * sizeof(char *));
|
|
else
|
|
values = (char **) palloc((CONNECTBY_NCOLS_NOBRANCH + serial_column) * sizeof(char *));
|
|
|
|
/* First time through, do a little setup */
|
|
if (level == 0)
|
|
{
|
|
/* root value is the one we initially start with */
|
|
values[0] = start_with;
|
|
|
|
/* root value has no parent */
|
|
values[1] = NULL;
|
|
|
|
/* root level is 0 */
|
|
sprintf(current_level, "%d", level);
|
|
values[2] = current_level;
|
|
|
|
/* root branch is just starting root value */
|
|
if (show_branch)
|
|
values[3] = start_with;
|
|
|
|
/* root starts the serial with 1 */
|
|
if (show_serial)
|
|
{
|
|
sprintf(serial_str, "%d", (*serial)++);
|
|
if (show_branch)
|
|
values[4] = serial_str;
|
|
else
|
|
values[3] = serial_str;
|
|
}
|
|
|
|
/* construct the tuple */
|
|
tuple = BuildTupleFromCStrings(attinmeta, values);
|
|
|
|
/* switch to long lived context while storing the tuple */
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* now store it */
|
|
tuplestore_puttuple(tupstore, tuple);
|
|
|
|
/* now reset the context */
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/* increment level */
|
|
level++;
|
|
}
|
|
|
|
/* Retrieve the desired rows */
|
|
ret = SPI_execute(sql.data, true, 0);
|
|
proc = SPI_processed;
|
|
|
|
/* Check for qualifying tuples */
|
|
if ((ret == SPI_OK_SELECT) && (proc > 0))
|
|
{
|
|
HeapTuple spi_tuple;
|
|
SPITupleTable *tuptable = SPI_tuptable;
|
|
TupleDesc spi_tupdesc = tuptable->tupdesc;
|
|
int i;
|
|
StringInfoData branchstr;
|
|
StringInfoData chk_branchstr;
|
|
StringInfoData chk_current_key;
|
|
|
|
/* First time through, do a little more setup */
|
|
if (level == 0)
|
|
{
|
|
/*
|
|
* Check that return tupdesc is compatible with the one we got
|
|
* from the query, but only at level 0 -- no need to check more
|
|
* than once
|
|
*/
|
|
|
|
if (!compatConnectbyTupleDescs(tupdesc, spi_tupdesc))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("Return and SQL tuple descriptions are " \
|
|
"incompatible.")));
|
|
}
|
|
|
|
for (i = 0; i < proc; i++)
|
|
{
|
|
/* start a new branch */
|
|
initStringInfo(&branchstr);
|
|
|
|
/* need these to check for recursion */
|
|
initStringInfo(&chk_branchstr);
|
|
initStringInfo(&chk_current_key);
|
|
|
|
/* initialize branch for this pass */
|
|
appendStringInfo(&branchstr, "%s", branch);
|
|
appendStringInfo(&chk_branchstr, "%s%s%s", branch_delim, branch, branch_delim);
|
|
|
|
/* get the next sql result tuple */
|
|
spi_tuple = tuptable->vals[i];
|
|
|
|
/* get the current key and parent */
|
|
current_key = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
|
|
appendStringInfo(&chk_current_key, "%s%s%s", branch_delim, current_key, branch_delim);
|
|
current_key_parent = pstrdup(SPI_getvalue(spi_tuple, spi_tupdesc, 2));
|
|
|
|
/* get the current level */
|
|
sprintf(current_level, "%d", level);
|
|
|
|
/* check to see if this key is also an ancestor */
|
|
if (strstr(chk_branchstr.data, chk_current_key.data))
|
|
elog(ERROR, "infinite recursion detected");
|
|
|
|
/* OK, extend the branch */
|
|
appendStringInfo(&branchstr, "%s%s", branch_delim, current_key);
|
|
current_branch = branchstr.data;
|
|
|
|
/* build a tuple */
|
|
values[0] = pstrdup(current_key);
|
|
values[1] = current_key_parent;
|
|
values[2] = current_level;
|
|
if (show_branch)
|
|
values[3] = current_branch;
|
|
if (show_serial)
|
|
{
|
|
sprintf(serial_str, "%d", (*serial)++);
|
|
if (show_branch)
|
|
values[4] = serial_str;
|
|
else
|
|
values[3] = serial_str;
|
|
}
|
|
|
|
tuple = BuildTupleFromCStrings(attinmeta, values);
|
|
|
|
xpfree(current_key);
|
|
xpfree(current_key_parent);
|
|
|
|
/* switch to long lived context while storing the tuple */
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
|
|
/* store the tuple for later use */
|
|
tuplestore_puttuple(tupstore, tuple);
|
|
|
|
/* now reset the context */
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
heap_freetuple(tuple);
|
|
|
|
/* recurse using current_key_parent as the new start_with */
|
|
tupstore = build_tuplestore_recursively(key_fld,
|
|
parent_key_fld,
|
|
relname,
|
|
orderby_fld,
|
|
branch_delim,
|
|
values[0],
|
|
current_branch,
|
|
level + 1,
|
|
serial,
|
|
max_depth,
|
|
show_branch,
|
|
show_serial,
|
|
per_query_ctx,
|
|
attinmeta,
|
|
tupstore);
|
|
|
|
/* reset branch for next pass */
|
|
xpfree(branchstr.data);
|
|
xpfree(chk_branchstr.data);
|
|
xpfree(chk_current_key.data);
|
|
}
|
|
}
|
|
|
|
return tupstore;
|
|
}
|
|
|
|
/*
|
|
* Check expected (query runtime) tupdesc suitable for Connectby
|
|
*/
|
|
static void
|
|
validateConnectbyTupleDesc(TupleDesc tupdesc, bool show_branch, bool show_serial)
|
|
{
|
|
int serial_column = 0;
|
|
|
|
if (show_serial)
|
|
serial_column = 1;
|
|
|
|
/* are there the correct number of columns */
|
|
if (show_branch)
|
|
{
|
|
if (tupdesc->natts != (CONNECTBY_NCOLS + serial_column))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("Query-specified return tuple has " \
|
|
"wrong number of columns.")));
|
|
}
|
|
else
|
|
{
|
|
if (tupdesc->natts != CONNECTBY_NCOLS_NOBRANCH + serial_column)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("Query-specified return tuple has " \
|
|
"wrong number of columns.")));
|
|
}
|
|
|
|
/* check that the types of the first two columns match */
|
|
if (tupdesc->attrs[0]->atttypid != tupdesc->attrs[1]->atttypid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("First two columns must be the same type.")));
|
|
|
|
/* check that the type of the third column is INT4 */
|
|
if (tupdesc->attrs[2]->atttypid != INT4OID)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("Third column must be type %s.",
|
|
format_type_be(INT4OID))));
|
|
|
|
/* check that the type of the fourth column is TEXT if applicable */
|
|
if (show_branch && tupdesc->attrs[3]->atttypid != TEXTOID)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("Fourth column must be type %s.",
|
|
format_type_be(TEXTOID))));
|
|
|
|
/* check that the type of the fifth column is INT4 */
|
|
if (show_branch && show_serial && tupdesc->attrs[4]->atttypid != INT4OID)
|
|
elog(ERROR, "query-specified return tuple not valid for Connectby: "
|
|
"fifth column must be type %s", format_type_be(INT4OID));
|
|
|
|
/* check that the type of the fifth column is INT4 */
|
|
if (!show_branch && show_serial && tupdesc->attrs[3]->atttypid != INT4OID)
|
|
elog(ERROR, "query-specified return tuple not valid for Connectby: "
|
|
"fourth column must be type %s", format_type_be(INT4OID));
|
|
|
|
/* OK, the tupdesc is valid for our purposes */
|
|
}
|
|
|
|
/*
|
|
* Check if spi sql tupdesc and return tupdesc are compatible
|
|
*/
|
|
static bool
|
|
compatConnectbyTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
|
|
{
|
|
Oid ret_atttypid;
|
|
Oid sql_atttypid;
|
|
|
|
/* check the key_fld types match */
|
|
ret_atttypid = ret_tupdesc->attrs[0]->atttypid;
|
|
sql_atttypid = sql_tupdesc->attrs[0]->atttypid;
|
|
if (ret_atttypid != sql_atttypid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("SQL key field datatype does " \
|
|
"not match return key field datatype.")));
|
|
|
|
/* check the parent_key_fld types match */
|
|
ret_atttypid = ret_tupdesc->attrs[1]->atttypid;
|
|
sql_atttypid = sql_tupdesc->attrs[1]->atttypid;
|
|
if (ret_atttypid != sql_atttypid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("SQL parent key field datatype does " \
|
|
"not match return parent key field datatype.")));
|
|
|
|
/* OK, the two tupdescs are compatible for our purposes */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Check if two tupdescs match in type of attributes
|
|
*/
|
|
static bool
|
|
compatCrosstabTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
|
|
{
|
|
int i;
|
|
Form_pg_attribute ret_attr;
|
|
Oid ret_atttypid;
|
|
Form_pg_attribute sql_attr;
|
|
Oid sql_atttypid;
|
|
|
|
/* check the rowid types match */
|
|
ret_atttypid = ret_tupdesc->attrs[0]->atttypid;
|
|
sql_atttypid = sql_tupdesc->attrs[0]->atttypid;
|
|
if (ret_atttypid != sql_atttypid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_SYNTAX_ERROR),
|
|
errmsg("invalid return type"),
|
|
errdetail("SQL rowid datatype does not match " \
|
|
"return rowid datatype.")));
|
|
|
|
/*
|
|
* - attribute [1] of the sql tuple is the category; no need to check it -
|
|
* attribute [2] of the sql tuple should match attributes [1] to [natts]
|
|
* of the return tuple
|
|
*/
|
|
sql_attr = sql_tupdesc->attrs[2];
|
|
for (i = 1; i < ret_tupdesc->natts; i++)
|
|
{
|
|
ret_attr = ret_tupdesc->attrs[i];
|
|
|
|
if (ret_attr->atttypid != sql_attr->atttypid)
|
|
return false;
|
|
}
|
|
|
|
/* OK, the two tupdescs are compatible for our purposes */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Return a properly quoted literal value.
|
|
* Uses quote_literal in quote.c
|
|
*/
|
|
static char *
|
|
quote_literal_cstr(char *rawstr)
|
|
{
|
|
text *rawstr_text;
|
|
text *result_text;
|
|
char *result;
|
|
|
|
rawstr_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(rawstr)));
|
|
result_text = DatumGetTextP(DirectFunctionCall1(quote_literal, PointerGetDatum(rawstr_text)));
|
|
result = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(result_text)));
|
|
|
|
return result;
|
|
}
|