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that the right flavors of largefile-related definitions are seen. Most of these changes are probably unnecessary, but better safe than sorry.
1090 lines
28 KiB
C
1090 lines
28 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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*
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* Copyright 2002 by 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 "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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static void validateConnectbyTupleDesc(TupleDesc tupdesc, bool show_branch);
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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 TupleDesc make_crosstab_tupledesc(TupleDesc spi_tupdesc,
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int num_catagories);
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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 *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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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 *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 max_depth,
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bool show_branch,
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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_ident_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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/*
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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 lower_bound, and float8 upper_bound
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* returns 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
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* 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
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* call. It will also be used to carry over the spare value we get
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* from the Box-Muller algorithm so that we only actually
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* calculate a new value 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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/*
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* we might actually get passed a negative number, but for this
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* purpose it doesn't matter, just cast it as an unsigned value
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*/
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srandom(PG_GETARG_UINT32(3));
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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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for (;;)
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{
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u1 = (float8) random() / (float8) RAND_MAX;
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u2 = (float8) random() / (float8) RAND_MAX;
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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 = pow(v1, 2) + pow(v2, 2);
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if (s >= 1.0)
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continue;
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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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*x1 = v1 * sqrt((-2.0 * log(s)) / s);
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*x2 = v2 * sqrt((-2.0 * log(s)) / s);
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}
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return;
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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.
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* 2. 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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* 3. 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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* 4. 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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TupleTableSlot *slot;
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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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Oid funcid = fcinfo->flinfo->fn_oid;
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Oid functypeid;
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char functyptype;
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TupleDesc tupdesc = NULL;
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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
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* 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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elog(ERROR, "crosstab: SPI_connect returned %d", ret);
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/* Retrieve the desired rows */
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ret = SPI_exec(sql, 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 the label or identifier for each row in the final
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* result 2. category the label or identifier for each column
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* in the final result 3. values the value for each column
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* in the final result
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*/
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if (spi_tupdesc->natts != 3)
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elog(ERROR, "crosstab: provided SQL must return 3 columns;"
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" a rowid, a category, and a values column");
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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 the typeid that represents our return type */
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functypeid = get_func_rettype(funcid);
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/* check typtype to see if we have a predetermined return type */
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functyptype = get_typtype(functypeid);
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if (functyptype == 'c')
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{
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/* Build a tuple description for a functypeid tuple */
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tupdesc = TypeGetTupleDesc(functypeid, NIL);
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}
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else if (functyptype == 'p' && functypeid == RECORDOID)
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{
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if (fcinfo->nargs != 2)
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elog(ERROR, "Wrong number of arguments specified for function");
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else
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{
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int num_catagories = PG_GETARG_INT32(1);
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tupdesc = make_crosstab_tupledesc(spi_tupdesc, num_catagories);
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}
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}
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else if (functyptype == 'b')
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elog(ERROR, "Invalid kind of return type specified for function");
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else
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elog(ERROR, "Unknown kind of return type specified for function");
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/*
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* Check that return tupdesc is compatible with the one we got
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* from ret_relname, at least based on number and type of
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* attributes
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*/
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if (!compatCrosstabTupleDescs(tupdesc, spi_tupdesc))
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elog(ERROR, "crosstab: return and sql tuple descriptions are"
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" incompatible");
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/* allocate a slot for a tuple with this tupdesc */
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slot = TupleDescGetSlot(tupdesc);
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/* assign slot to function context */
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funcctx->slot = slot;
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/*
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* Generate attribute metadata needed later to produce tuples from
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* raw C strings
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*/
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attinmeta = TupleDescGetAttInMetadata(tupdesc);
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funcctx->attinmeta = attinmeta;
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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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* 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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/* stuff done on every call of the function */
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funcctx = SRF_PERCALL_SETUP();
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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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/* return slot for our tuple */
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slot = funcctx->slot;
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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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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;
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char **values;
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bool allnulls = true;
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while (true)
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{
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/* allocate space */
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values = (char **) palloc((1 + num_categories) * sizeof(char *));
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/* 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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* now loop through the sql results and assign each value in
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* sequence to the next category
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*/
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for (i = 0; i < num_categories; i++)
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{
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HeapTuple spi_tuple;
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char *rowid = NULL;
|
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/* see if we've gone too far already */
|
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if (call_cntr >= max_calls)
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break;
|
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|
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/* get the next sql result tuple */
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spi_tuple = spi_tuptable->vals[call_cntr];
|
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|
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/* get the rowid from the current sql result tuple */
|
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rowid = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
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|
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/*
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* If this is the first pass through the values for this
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* rowid set it, otherwise make sure it hasn't changed on
|
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* us. Also check to see if the rowid is the same as that
|
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* of the last tuple sent -- if so, skip this tuple
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* entirely
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*/
|
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if (i == 0)
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values[0] = pstrdup(rowid);
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|
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if ((rowid != NULL) && (strcmp(rowid, values[0]) == 0))
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{
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if ((lastrowid != NULL) && (strcmp(rowid, lastrowid) == 0))
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break;
|
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else if (allnulls == true)
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allnulls = false;
|
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|
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/*
|
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* Get the next category item value, which is alway
|
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* attribute number three.
|
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*
|
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* Be careful to sssign the value to the array index
|
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* based on which category we are presently
|
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* processing.
|
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*/
|
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values[1 + i] = SPI_getvalue(spi_tuple, spi_tupdesc, 3);
|
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|
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/*
|
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* increment the counter since we consume a row for
|
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* each category, but not for last pass because the
|
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* API will do that for us
|
|
*/
|
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if (i < (num_categories - 1))
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call_cntr = ++funcctx->call_cntr;
|
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}
|
|
else
|
|
{
|
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/*
|
|
* 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 = TupleGetDatum(slot, 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);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* connectby_text - produce a result set from a hierarchical (parent/child)
|
|
* table.
|
|
*
|
|
* e.g. given table foo:
|
|
*
|
|
* keyid parent_keyid
|
|
* ------+--------------
|
|
* row1 NULL
|
|
* row2 row1
|
|
* row3 row1
|
|
* row4 row2
|
|
* row5 row2
|
|
* row6 row4
|
|
* row7 row3
|
|
* row8 row6
|
|
* row9 row5
|
|
*
|
|
*
|
|
* connectby(text relname, text keyid_fld, text parent_keyid_fld,
|
|
* text start_with, int max_depth [, text branch_delim])
|
|
* connectby('foo', 'keyid', 'parent_keyid', 'row2', 0, '~') returns:
|
|
*
|
|
* keyid parent_id level branch
|
|
* ------+-----------+--------+-----------------------
|
|
* row2 NULL 0 row2
|
|
* row4 row2 1 row2~row4
|
|
* row6 row4 2 row2~row4~row6
|
|
* row8 row6 3 row2~row4~row6~row8
|
|
* row5 row2 1 row2~row5
|
|
* row9 row5 2 row2~row5~row9
|
|
*
|
|
*/
|
|
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;
|
|
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
|
|
TupleDesc tupdesc;
|
|
AttInMetadata *attinmeta;
|
|
MemoryContext per_query_ctx;
|
|
MemoryContext oldcontext;
|
|
|
|
if (fcinfo->nargs == 6)
|
|
{
|
|
branch_delim = GET_STR(PG_GETARG_TEXT_P(5));
|
|
show_branch = true;
|
|
}
|
|
|
|
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);
|
|
|
|
/* OK, use it then */
|
|
attinmeta = TupleDescGetAttInMetadata(tupdesc);
|
|
|
|
/* check to see if caller supports us returning a tuplestore */
|
|
if (!rsinfo->allowedModes & SFRM_Materialize)
|
|
elog(ERROR, "connectby requires Materialize mode, but it is not "
|
|
"allowed in this context");
|
|
|
|
/* OK, go to work */
|
|
rsinfo->returnMode = SFRM_Materialize;
|
|
rsinfo->setResult = connectby(relname,
|
|
key_fld,
|
|
parent_key_fld,
|
|
branch_delim,
|
|
start_with,
|
|
max_depth,
|
|
show_branch,
|
|
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 *branch_delim,
|
|
char *start_with,
|
|
int max_depth,
|
|
bool show_branch,
|
|
MemoryContext per_query_ctx,
|
|
AttInMetadata *attinmeta)
|
|
{
|
|
Tuplestorestate *tupstore = NULL;
|
|
int ret;
|
|
MemoryContext oldcontext;
|
|
|
|
/* Connect to SPI manager */
|
|
if ((ret = SPI_connect()) < 0)
|
|
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, SortMem);
|
|
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
/* now go get the whole tree */
|
|
tupstore = build_tuplestore_recursively(key_fld,
|
|
parent_key_fld,
|
|
relname,
|
|
branch_delim,
|
|
start_with,
|
|
start_with, /* current_branch */
|
|
0, /* initial level is 0 */
|
|
max_depth,
|
|
show_branch,
|
|
per_query_ctx,
|
|
attinmeta,
|
|
tupstore);
|
|
|
|
SPI_finish();
|
|
|
|
oldcontext = MemoryContextSwitchTo(per_query_ctx);
|
|
tuplestore_donestoring(tupstore);
|
|
MemoryContextSwitchTo(oldcontext);
|
|
|
|
return tupstore;
|
|
}
|
|
|
|
static Tuplestorestate *
|
|
build_tuplestore_recursively(char *key_fld,
|
|
char *parent_key_fld,
|
|
char *relname,
|
|
char *branch_delim,
|
|
char *start_with,
|
|
char *branch,
|
|
int level,
|
|
int max_depth,
|
|
bool show_branch,
|
|
MemoryContext per_query_ctx,
|
|
AttInMetadata *attinmeta,
|
|
Tuplestorestate *tupstore)
|
|
{
|
|
TupleDesc tupdesc = attinmeta->tupdesc;
|
|
MemoryContext oldcontext;
|
|
StringInfo sql = makeStringInfo();
|
|
int ret;
|
|
int proc;
|
|
|
|
if (max_depth > 0 && level > max_depth)
|
|
return tupstore;
|
|
|
|
/* Build initial sql statement */
|
|
appendStringInfo(sql, "SELECT %s, %s FROM %s WHERE %s = '%s' AND %s IS NOT NULL",
|
|
quote_ident_cstr(key_fld),
|
|
quote_ident_cstr(parent_key_fld),
|
|
quote_ident_cstr(relname),
|
|
quote_ident_cstr(parent_key_fld),
|
|
start_with,
|
|
quote_ident_cstr(key_fld));
|
|
|
|
/* Retrieve the desired rows */
|
|
ret = SPI_exec(sql->data, 0);
|
|
proc = SPI_processed;
|
|
|
|
/* Check for qualifying tuples */
|
|
if ((ret == SPI_OK_SELECT) && (proc > 0))
|
|
{
|
|
HeapTuple tuple;
|
|
HeapTuple spi_tuple;
|
|
SPITupleTable *tuptable = SPI_tuptable;
|
|
TupleDesc spi_tupdesc = tuptable->tupdesc;
|
|
int i;
|
|
char *current_key;
|
|
char *current_key_parent;
|
|
char current_level[INT32_STRLEN];
|
|
char *current_branch;
|
|
char **values;
|
|
|
|
if (show_branch)
|
|
values = (char **) palloc(CONNECTBY_NCOLS * sizeof(char *));
|
|
else
|
|
values = (char **) palloc(CONNECTBY_NCOLS_NOBRANCH * sizeof(char *));
|
|
|
|
/* First time through, do a little 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))
|
|
elog(ERROR, "connectby: return and sql tuple descriptions are "
|
|
"incompatible");
|
|
|
|
/* 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;
|
|
|
|
/* 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++;
|
|
}
|
|
|
|
for (i = 0; i < proc; i++)
|
|
{
|
|
StringInfo branchstr = NULL;
|
|
|
|
/* start a new branch */
|
|
if (show_branch)
|
|
{
|
|
branchstr = makeStringInfo();
|
|
appendStringInfo(branchstr, "%s", branch);
|
|
}
|
|
|
|
/* 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);
|
|
current_key_parent = pstrdup(SPI_getvalue(spi_tuple, spi_tupdesc, 2));
|
|
|
|
/* get the current level */
|
|
sprintf(current_level, "%d", level);
|
|
|
|
/* extend the branch */
|
|
if (show_branch)
|
|
{
|
|
appendStringInfo(branchstr, "%s%s", branch_delim, current_key);
|
|
current_branch = branchstr->data;
|
|
}
|
|
else
|
|
current_branch = NULL;
|
|
|
|
/* build a tuple */
|
|
values[0] = pstrdup(current_key);
|
|
values[1] = current_key_parent;
|
|
values[2] = current_level;
|
|
if (show_branch)
|
|
values[3] = current_branch;
|
|
|
|
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,
|
|
branch_delim,
|
|
values[0],
|
|
current_branch,
|
|
level + 1,
|
|
max_depth,
|
|
show_branch,
|
|
per_query_ctx,
|
|
attinmeta,
|
|
tupstore);
|
|
}
|
|
}
|
|
|
|
return tupstore;
|
|
}
|
|
|
|
/*
|
|
* Check expected (query runtime) tupdesc suitable for Connectby
|
|
*/
|
|
static void
|
|
validateConnectbyTupleDesc(TupleDesc tupdesc, bool show_branch)
|
|
{
|
|
/* are there the correct number of columns */
|
|
if (show_branch)
|
|
{
|
|
if (tupdesc->natts != CONNECTBY_NCOLS)
|
|
elog(ERROR, "Query-specified return tuple not valid for Connectby: "
|
|
"wrong number of columns");
|
|
}
|
|
else
|
|
{
|
|
if (tupdesc->natts != CONNECTBY_NCOLS_NOBRANCH)
|
|
elog(ERROR, "Query-specified return tuple not valid for Connectby: "
|
|
"wrong number of columns");
|
|
}
|
|
|
|
/* check that the types of the first two columns match */
|
|
if (tupdesc->attrs[0]->atttypid != tupdesc->attrs[1]->atttypid)
|
|
elog(ERROR, "Query-specified return tuple not valid for Connectby: "
|
|
"first two columns must be the same type");
|
|
|
|
/* check that the type of the third column is INT4 */
|
|
if (tupdesc->attrs[2]->atttypid != INT4OID)
|
|
elog(ERROR, "Query-specified return tuple not valid for Connectby: "
|
|
"third column must be type %s", format_type_be(INT4OID));
|
|
|
|
/* check that the type of the forth column is TEXT if applicable */
|
|
if (show_branch && tupdesc->attrs[3]->atttypid != TEXTOID)
|
|
elog(ERROR, "Query-specified return tuple not valid for Connectby: "
|
|
"third column must be type %s", format_type_be(TEXTOID));
|
|
|
|
/* 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)
|
|
elog(ERROR, "compatConnectbyTupleDescs: 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)
|
|
elog(ERROR, "compatConnectbyTupleDescs: 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)
|
|
elog(ERROR, "compatCrosstabTupleDescs: 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;
|
|
}
|
|
|
|
static TupleDesc
|
|
make_crosstab_tupledesc(TupleDesc spi_tupdesc, int num_catagories)
|
|
{
|
|
Form_pg_attribute sql_attr;
|
|
Oid sql_atttypid;
|
|
TupleDesc tupdesc;
|
|
int natts;
|
|
AttrNumber attnum;
|
|
char attname[NAMEDATALEN];
|
|
int i;
|
|
|
|
/*
|
|
* We need to build a tuple description with one column for the
|
|
* rowname, and num_catagories columns for the values. Each must be of
|
|
* the same type as the corresponding spi result input column.
|
|
*/
|
|
natts = num_catagories + 1;
|
|
tupdesc = CreateTemplateTupleDesc(natts, false);
|
|
|
|
/* first the rowname column */
|
|
attnum = 1;
|
|
|
|
sql_attr = spi_tupdesc->attrs[0];
|
|
sql_atttypid = sql_attr->atttypid;
|
|
|
|
strcpy(attname, "rowname");
|
|
|
|
TupleDescInitEntry(tupdesc, attnum, attname, sql_atttypid,
|
|
-1, 0, false);
|
|
|
|
/* now the catagory values columns */
|
|
sql_attr = spi_tupdesc->attrs[2];
|
|
sql_atttypid = sql_attr->atttypid;
|
|
|
|
for (i = 0; i < num_catagories; i++)
|
|
{
|
|
attnum++;
|
|
|
|
sprintf(attname, "category_%d", i + 1);
|
|
TupleDescInitEntry(tupdesc, attnum, attname, sql_atttypid,
|
|
-1, 0, false);
|
|
}
|
|
|
|
return tupdesc;
|
|
}
|
|
|
|
/*
|
|
* Return a properly quoted identifier.
|
|
* Uses quote_ident in quote.c
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*/
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static char *
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quote_ident_cstr(char *rawstr)
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{
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text *rawstr_text;
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text *result_text;
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char *result;
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rawstr_text = DatumGetTextP(DirectFunctionCall1(textin, CStringGetDatum(rawstr)));
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result_text = DatumGetTextP(DirectFunctionCall1(quote_ident, PointerGetDatum(rawstr_text)));
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result = DatumGetCString(DirectFunctionCall1(textout, PointerGetDatum(result_text)));
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return result;
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}
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