1 /*
2 * contrib/tablefunc/tablefunc.c
3 *
4 *
5 * tablefunc
6 *
7 * Sample to demonstrate C functions which return setof scalar
8 * and setof composite.
9 * Joe Conway <mail@joeconway.com>
10 * And contributors:
11 * Nabil Sayegh <postgresql@e-trolley.de>
12 *
13 * Copyright (c) 2002-2019, PostgreSQL Global Development Group
14 *
15 * Permission to use, copy, modify, and distribute this software and its
16 * documentation for any purpose, without fee, and without a written agreement
17 * is hereby granted, provided that the above copyright notice and this
18 * paragraph and the following two paragraphs appear in all copies.
19 *
20 * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY PARTY FOR
21 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
22 * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
23 * DOCUMENTATION, EVEN IF THE AUTHOR OR DISTRIBUTORS HAVE BEEN ADVISED OF THE
24 * POSSIBILITY OF SUCH DAMAGE.
25 *
26 * THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
27 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
28 * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
29 * ON AN "AS IS" BASIS, AND THE AUTHOR AND DISTRIBUTORS HAS NO OBLIGATIONS TO
30 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
31 *
32 */
33 #include "postgres.h"
34
35 #include <math.h>
36
37 #include "access/htup_details.h"
38 #include "catalog/pg_type.h"
39 #include "executor/spi.h"
40 #include "funcapi.h"
41 #include "lib/stringinfo.h"
42 #include "miscadmin.h"
43 #include "utils/builtins.h"
44
45 #include "tablefunc.h"
46
47 PG_MODULE_MAGIC;
48
49 static HTAB *load_categories_hash(char *cats_sql, MemoryContext per_query_ctx);
50 static Tuplestorestate *get_crosstab_tuplestore(char *sql,
51 HTAB *crosstab_hash,
52 TupleDesc tupdesc,
53 MemoryContext per_query_ctx,
54 bool randomAccess);
55 static void validateConnectbyTupleDesc(TupleDesc tupdesc, bool show_branch, bool show_serial);
56 static bool compatCrosstabTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2);
57 static void compatConnectbyTupleDescs(TupleDesc tupdesc1, TupleDesc tupdesc2);
58 static void get_normal_pair(float8 *x1, float8 *x2);
59 static Tuplestorestate *connectby(char *relname,
60 char *key_fld,
61 char *parent_key_fld,
62 char *orderby_fld,
63 char *branch_delim,
64 char *start_with,
65 int max_depth,
66 bool show_branch,
67 bool show_serial,
68 MemoryContext per_query_ctx,
69 bool randomAccess,
70 AttInMetadata *attinmeta);
71 static void build_tuplestore_recursively(char *key_fld,
72 char *parent_key_fld,
73 char *relname,
74 char *orderby_fld,
75 char *branch_delim,
76 char *start_with,
77 char *branch,
78 int level,
79 int *serial,
80 int max_depth,
81 bool show_branch,
82 bool show_serial,
83 MemoryContext per_query_ctx,
84 AttInMetadata *attinmeta,
85 Tuplestorestate *tupstore);
86
87 typedef struct
88 {
89 float8 mean; /* mean of the distribution */
90 float8 stddev; /* stddev of the distribution */
91 float8 carry_val; /* hold second generated value */
92 bool use_carry; /* use second generated value */
93 } normal_rand_fctx;
94
95 #define xpfree(var_) \
96 do { \
97 if (var_ != NULL) \
98 { \
99 pfree(var_); \
100 var_ = NULL; \
101 } \
102 } while (0)
103
104 #define xpstrdup(tgtvar_, srcvar_) \
105 do { \
106 if (srcvar_) \
107 tgtvar_ = pstrdup(srcvar_); \
108 else \
109 tgtvar_ = NULL; \
110 } while (0)
111
112 #define xstreq(tgtvar_, srcvar_) \
113 (((tgtvar_ == NULL) && (srcvar_ == NULL)) || \
114 ((tgtvar_ != NULL) && (srcvar_ != NULL) && (strcmp(tgtvar_, srcvar_) == 0)))
115
116 /* sign, 10 digits, '\0' */
117 #define INT32_STRLEN 12
118
119 /* stored info for a crosstab category */
120 typedef struct crosstab_cat_desc
121 {
122 char *catname; /* full category name */
123 uint64 attidx; /* zero based */
124 } crosstab_cat_desc;
125
126 #define MAX_CATNAME_LEN NAMEDATALEN
127 #define INIT_CATS 64
128
129 #define crosstab_HashTableLookup(HASHTAB, CATNAME, CATDESC) \
130 do { \
131 crosstab_HashEnt *hentry; char key[MAX_CATNAME_LEN]; \
132 \
133 MemSet(key, 0, MAX_CATNAME_LEN); \
134 snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATNAME); \
135 hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
136 key, HASH_FIND, NULL); \
137 if (hentry) \
138 CATDESC = hentry->catdesc; \
139 else \
140 CATDESC = NULL; \
141 } while(0)
142
143 #define crosstab_HashTableInsert(HASHTAB, CATDESC) \
144 do { \
145 crosstab_HashEnt *hentry; bool found; char key[MAX_CATNAME_LEN]; \
146 \
147 MemSet(key, 0, MAX_CATNAME_LEN); \
148 snprintf(key, MAX_CATNAME_LEN - 1, "%s", CATDESC->catname); \
149 hentry = (crosstab_HashEnt*) hash_search(HASHTAB, \
150 key, HASH_ENTER, &found); \
151 if (found) \
152 ereport(ERROR, \
153 (errcode(ERRCODE_DUPLICATE_OBJECT), \
154 errmsg("duplicate category name"))); \
155 hentry->catdesc = CATDESC; \
156 } while(0)
157
158 /* hash table */
159 typedef struct crosstab_hashent
160 {
161 char internal_catname[MAX_CATNAME_LEN];
162 crosstab_cat_desc *catdesc;
163 } crosstab_HashEnt;
164
165 /*
166 * normal_rand - return requested number of random values
167 * with a Gaussian (Normal) distribution.
168 *
169 * inputs are int numvals, float8 mean, and float8 stddev
170 * returns setof float8
171 */
172 PG_FUNCTION_INFO_V1(normal_rand);
173 Datum
normal_rand(PG_FUNCTION_ARGS)174 normal_rand(PG_FUNCTION_ARGS)
175 {
176 FuncCallContext *funcctx;
177 uint64 call_cntr;
178 uint64 max_calls;
179 normal_rand_fctx *fctx;
180 float8 mean;
181 float8 stddev;
182 float8 carry_val;
183 bool use_carry;
184 MemoryContext oldcontext;
185
186 /* stuff done only on the first call of the function */
187 if (SRF_IS_FIRSTCALL())
188 {
189 /* create a function context for cross-call persistence */
190 funcctx = SRF_FIRSTCALL_INIT();
191
192 /*
193 * switch to memory context appropriate for multiple function calls
194 */
195 oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
196
197 /* total number of tuples to be returned */
198 funcctx->max_calls = PG_GETARG_UINT32(0);
199
200 /* allocate memory for user context */
201 fctx = (normal_rand_fctx *) palloc(sizeof(normal_rand_fctx));
202
203 /*
204 * Use fctx to keep track of upper and lower bounds from call to call.
205 * It will also be used to carry over the spare value we get from the
206 * Box-Muller algorithm so that we only actually calculate a new value
207 * every other call.
208 */
209 fctx->mean = PG_GETARG_FLOAT8(1);
210 fctx->stddev = PG_GETARG_FLOAT8(2);
211 fctx->carry_val = 0;
212 fctx->use_carry = false;
213
214 funcctx->user_fctx = fctx;
215
216 MemoryContextSwitchTo(oldcontext);
217 }
218
219 /* stuff done on every call of the function */
220 funcctx = SRF_PERCALL_SETUP();
221
222 call_cntr = funcctx->call_cntr;
223 max_calls = funcctx->max_calls;
224 fctx = funcctx->user_fctx;
225 mean = fctx->mean;
226 stddev = fctx->stddev;
227 carry_val = fctx->carry_val;
228 use_carry = fctx->use_carry;
229
230 if (call_cntr < max_calls) /* do when there is more left to send */
231 {
232 float8 result;
233
234 if (use_carry)
235 {
236 /*
237 * reset use_carry and use second value obtained on last pass
238 */
239 fctx->use_carry = false;
240 result = carry_val;
241 }
242 else
243 {
244 float8 normval_1;
245 float8 normval_2;
246
247 /* Get the next two normal values */
248 get_normal_pair(&normval_1, &normval_2);
249
250 /* use the first */
251 result = mean + (stddev * normval_1);
252
253 /* and save the second */
254 fctx->carry_val = mean + (stddev * normval_2);
255 fctx->use_carry = true;
256 }
257
258 /* send the result */
259 SRF_RETURN_NEXT(funcctx, Float8GetDatum(result));
260 }
261 else
262 /* do when there is no more left */
263 SRF_RETURN_DONE(funcctx);
264 }
265
266 /*
267 * get_normal_pair()
268 * Assigns normally distributed (Gaussian) values to a pair of provided
269 * parameters, with mean 0, standard deviation 1.
270 *
271 * This routine implements Algorithm P (Polar method for normal deviates)
272 * from Knuth's _The_Art_of_Computer_Programming_, Volume 2, 3rd ed., pages
273 * 122-126. Knuth cites his source as "The polar method", G. E. P. Box, M. E.
274 * Muller, and G. Marsaglia, _Annals_Math,_Stat._ 29 (1958), 610-611.
275 *
276 */
277 static void
get_normal_pair(float8 * x1,float8 * x2)278 get_normal_pair(float8 *x1, float8 *x2)
279 {
280 float8 u1,
281 u2,
282 v1,
283 v2,
284 s;
285
286 do
287 {
288 u1 = (float8) random() / (float8) MAX_RANDOM_VALUE;
289 u2 = (float8) random() / (float8) MAX_RANDOM_VALUE;
290
291 v1 = (2.0 * u1) - 1.0;
292 v2 = (2.0 * u2) - 1.0;
293
294 s = v1 * v1 + v2 * v2;
295 } while (s >= 1.0);
296
297 if (s == 0)
298 {
299 *x1 = 0;
300 *x2 = 0;
301 }
302 else
303 {
304 s = sqrt((-2.0 * log(s)) / s);
305 *x1 = v1 * s;
306 *x2 = v2 * s;
307 }
308 }
309
310 /*
311 * crosstab - create a crosstab of rowids and values columns from a
312 * SQL statement returning one rowid column, one category column,
313 * and one value column.
314 *
315 * e.g. given sql which produces:
316 *
317 * rowid cat value
318 * ------+-------+-------
319 * row1 cat1 val1
320 * row1 cat2 val2
321 * row1 cat3 val3
322 * row1 cat4 val4
323 * row2 cat1 val5
324 * row2 cat2 val6
325 * row2 cat3 val7
326 * row2 cat4 val8
327 *
328 * crosstab returns:
329 * <===== values columns =====>
330 * rowid cat1 cat2 cat3 cat4
331 * ------+-------+-------+-------+-------
332 * row1 val1 val2 val3 val4
333 * row2 val5 val6 val7 val8
334 *
335 * NOTES:
336 * 1. SQL result must be ordered by 1,2.
337 * 2. The number of values columns depends on the tuple description
338 * of the function's declared return type. The return type's columns
339 * must match the datatypes of the SQL query's result. The datatype
340 * of the category column can be anything, however.
341 * 3. Missing values (i.e. not enough adjacent rows of same rowid to
342 * fill the number of result values columns) are filled in with nulls.
343 * 4. Extra values (i.e. too many adjacent rows of same rowid to fill
344 * the number of result values columns) are skipped.
345 * 5. Rows with all nulls in the values columns are skipped.
346 */
347 PG_FUNCTION_INFO_V1(crosstab);
348 Datum
crosstab(PG_FUNCTION_ARGS)349 crosstab(PG_FUNCTION_ARGS)
350 {
351 char *sql = text_to_cstring(PG_GETARG_TEXT_PP(0));
352 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
353 Tuplestorestate *tupstore;
354 TupleDesc tupdesc;
355 uint64 call_cntr;
356 uint64 max_calls;
357 AttInMetadata *attinmeta;
358 SPITupleTable *spi_tuptable;
359 TupleDesc spi_tupdesc;
360 bool firstpass;
361 char *lastrowid;
362 int i;
363 int num_categories;
364 MemoryContext per_query_ctx;
365 MemoryContext oldcontext;
366 int ret;
367 uint64 proc;
368
369 /* check to see if caller supports us returning a tuplestore */
370 if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
371 ereport(ERROR,
372 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
373 errmsg("set-valued function called in context that cannot accept a set")));
374 if (!(rsinfo->allowedModes & SFRM_Materialize))
375 ereport(ERROR,
376 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
377 errmsg("materialize mode required, but it is not " \
378 "allowed in this context")));
379
380 per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
381
382 /* Connect to SPI manager */
383 if ((ret = SPI_connect()) < 0)
384 /* internal error */
385 elog(ERROR, "crosstab: SPI_connect returned %d", ret);
386
387 /* Retrieve the desired rows */
388 ret = SPI_execute(sql, true, 0);
389 proc = SPI_processed;
390
391 /* If no qualifying tuples, fall out early */
392 if (ret != SPI_OK_SELECT || proc == 0)
393 {
394 SPI_finish();
395 rsinfo->isDone = ExprEndResult;
396 PG_RETURN_NULL();
397 }
398
399 spi_tuptable = SPI_tuptable;
400 spi_tupdesc = spi_tuptable->tupdesc;
401
402 /*----------
403 * The provided SQL query must always return three columns.
404 *
405 * 1. rowname
406 * the label or identifier for each row in the final result
407 * 2. category
408 * the label or identifier for each column in the final result
409 * 3. values
410 * the value for each column in the final result
411 *----------
412 */
413 if (spi_tupdesc->natts != 3)
414 ereport(ERROR,
415 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
416 errmsg("invalid source data SQL statement"),
417 errdetail("The provided SQL must return 3 "
418 "columns: rowid, category, and values.")));
419
420 /* get a tuple descriptor for our result type */
421 switch (get_call_result_type(fcinfo, NULL, &tupdesc))
422 {
423 case TYPEFUNC_COMPOSITE:
424 /* success */
425 break;
426 case TYPEFUNC_RECORD:
427 /* failed to determine actual type of RECORD */
428 ereport(ERROR,
429 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
430 errmsg("function returning record called in context "
431 "that cannot accept type record")));
432 break;
433 default:
434 /* result type isn't composite */
435 ereport(ERROR,
436 (errcode(ERRCODE_DATATYPE_MISMATCH),
437 errmsg("return type must be a row type")));
438 break;
439 }
440
441 /*
442 * Check that return tupdesc is compatible with the data we got from SPI,
443 * at least based on number and type of attributes
444 */
445 if (!compatCrosstabTupleDescs(tupdesc, spi_tupdesc))
446 ereport(ERROR,
447 (errcode(ERRCODE_SYNTAX_ERROR),
448 errmsg("return and sql tuple descriptions are " \
449 "incompatible")));
450
451 /*
452 * switch to long-lived memory context
453 */
454 oldcontext = MemoryContextSwitchTo(per_query_ctx);
455
456 /* make sure we have a persistent copy of the result tupdesc */
457 tupdesc = CreateTupleDescCopy(tupdesc);
458
459 /* initialize our tuplestore in long-lived context */
460 tupstore =
461 tuplestore_begin_heap(rsinfo->allowedModes & SFRM_Materialize_Random,
462 false, work_mem);
463
464 MemoryContextSwitchTo(oldcontext);
465
466 /*
467 * Generate attribute metadata needed later to produce tuples from raw C
468 * strings
469 */
470 attinmeta = TupleDescGetAttInMetadata(tupdesc);
471
472 /* total number of tuples to be examined */
473 max_calls = proc;
474
475 /* the return tuple always must have 1 rowid + num_categories columns */
476 num_categories = tupdesc->natts - 1;
477
478 firstpass = true;
479 lastrowid = NULL;
480
481 for (call_cntr = 0; call_cntr < max_calls; call_cntr++)
482 {
483 bool skip_tuple = false;
484 char **values;
485
486 /* allocate and zero space */
487 values = (char **) palloc0((1 + num_categories) * sizeof(char *));
488
489 /*
490 * now loop through the sql results and assign each value in sequence
491 * to the next category
492 */
493 for (i = 0; i < num_categories; i++)
494 {
495 HeapTuple spi_tuple;
496 char *rowid;
497
498 /* see if we've gone too far already */
499 if (call_cntr >= max_calls)
500 break;
501
502 /* get the next sql result tuple */
503 spi_tuple = spi_tuptable->vals[call_cntr];
504
505 /* get the rowid from the current sql result tuple */
506 rowid = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
507
508 /*
509 * If this is the first pass through the values for this rowid,
510 * set the first column to rowid
511 */
512 if (i == 0)
513 {
514 xpstrdup(values[0], rowid);
515
516 /*
517 * Check to see if the rowid is the same as that of the last
518 * tuple sent -- if so, skip this tuple entirely
519 */
520 if (!firstpass && xstreq(lastrowid, rowid))
521 {
522 xpfree(rowid);
523 skip_tuple = true;
524 break;
525 }
526 }
527
528 /*
529 * If rowid hasn't changed on us, continue building the output
530 * tuple.
531 */
532 if (xstreq(rowid, values[0]))
533 {
534 /*
535 * Get the next category item value, which is always attribute
536 * number three.
537 *
538 * Be careful to assign the value to the array index based on
539 * which category we are presently processing.
540 */
541 values[1 + i] = SPI_getvalue(spi_tuple, spi_tupdesc, 3);
542
543 /*
544 * increment the counter since we consume a row for each
545 * category, but not for last pass because the outer loop will
546 * do that for us
547 */
548 if (i < (num_categories - 1))
549 call_cntr++;
550 xpfree(rowid);
551 }
552 else
553 {
554 /*
555 * We'll fill in NULLs for the missing values, but we need to
556 * decrement the counter since this sql result row doesn't
557 * belong to the current output tuple.
558 */
559 call_cntr--;
560 xpfree(rowid);
561 break;
562 }
563 }
564
565 if (!skip_tuple)
566 {
567 HeapTuple tuple;
568
569 /* build the tuple and store it */
570 tuple = BuildTupleFromCStrings(attinmeta, values);
571 tuplestore_puttuple(tupstore, tuple);
572 heap_freetuple(tuple);
573 }
574
575 /* Remember current rowid */
576 xpfree(lastrowid);
577 xpstrdup(lastrowid, values[0]);
578 firstpass = false;
579
580 /* Clean up */
581 for (i = 0; i < num_categories + 1; i++)
582 if (values[i] != NULL)
583 pfree(values[i]);
584 pfree(values);
585 }
586
587 /* let the caller know we're sending back a tuplestore */
588 rsinfo->returnMode = SFRM_Materialize;
589 rsinfo->setResult = tupstore;
590 rsinfo->setDesc = tupdesc;
591
592 /* release SPI related resources (and return to caller's context) */
593 SPI_finish();
594
595 return (Datum) 0;
596 }
597
598 /*
599 * crosstab_hash - reimplement crosstab as materialized function and
600 * properly deal with missing values (i.e. don't pack remaining
601 * values to the left)
602 *
603 * crosstab - create a crosstab of rowids and values columns from a
604 * SQL statement returning one rowid column, one category column,
605 * and one value column.
606 *
607 * e.g. given sql which produces:
608 *
609 * rowid cat value
610 * ------+-------+-------
611 * row1 cat1 val1
612 * row1 cat2 val2
613 * row1 cat4 val4
614 * row2 cat1 val5
615 * row2 cat2 val6
616 * row2 cat3 val7
617 * row2 cat4 val8
618 *
619 * crosstab returns:
620 * <===== values columns =====>
621 * rowid cat1 cat2 cat3 cat4
622 * ------+-------+-------+-------+-------
623 * row1 val1 val2 null val4
624 * row2 val5 val6 val7 val8
625 *
626 * NOTES:
627 * 1. SQL result must be ordered by 1.
628 * 2. The number of values columns depends on the tuple description
629 * of the function's declared return type.
630 * 3. Missing values (i.e. missing category) are filled in with nulls.
631 * 4. Extra values (i.e. not in category results) are skipped.
632 */
633 PG_FUNCTION_INFO_V1(crosstab_hash);
634 Datum
crosstab_hash(PG_FUNCTION_ARGS)635 crosstab_hash(PG_FUNCTION_ARGS)
636 {
637 char *sql = text_to_cstring(PG_GETARG_TEXT_PP(0));
638 char *cats_sql = text_to_cstring(PG_GETARG_TEXT_PP(1));
639 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
640 TupleDesc tupdesc;
641 MemoryContext per_query_ctx;
642 MemoryContext oldcontext;
643 HTAB *crosstab_hash;
644
645 /* check to see if caller supports us returning a tuplestore */
646 if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
647 ereport(ERROR,
648 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
649 errmsg("set-valued function called in context that cannot accept a set")));
650 if (!(rsinfo->allowedModes & SFRM_Materialize) ||
651 rsinfo->expectedDesc == NULL)
652 ereport(ERROR,
653 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
654 errmsg("materialize mode required, but it is not " \
655 "allowed in this context")));
656
657 per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
658 oldcontext = MemoryContextSwitchTo(per_query_ctx);
659
660 /* get the requested return tuple description */
661 tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
662
663 /*
664 * Check to make sure we have a reasonable tuple descriptor
665 *
666 * Note we will attempt to coerce the values into whatever the return
667 * attribute type is and depend on the "in" function to complain if
668 * needed.
669 */
670 if (tupdesc->natts < 2)
671 ereport(ERROR,
672 (errcode(ERRCODE_SYNTAX_ERROR),
673 errmsg("query-specified return tuple and " \
674 "crosstab function are not compatible")));
675
676 /* load up the categories hash table */
677 crosstab_hash = load_categories_hash(cats_sql, per_query_ctx);
678
679 /* let the caller know we're sending back a tuplestore */
680 rsinfo->returnMode = SFRM_Materialize;
681
682 /* now go build it */
683 rsinfo->setResult = get_crosstab_tuplestore(sql,
684 crosstab_hash,
685 tupdesc,
686 per_query_ctx,
687 rsinfo->allowedModes & SFRM_Materialize_Random);
688
689 /*
690 * SFRM_Materialize mode expects us to return a NULL Datum. The actual
691 * tuples are in our tuplestore and passed back through rsinfo->setResult.
692 * rsinfo->setDesc is set to the tuple description that we actually used
693 * to build our tuples with, so the caller can verify we did what it was
694 * expecting.
695 */
696 rsinfo->setDesc = tupdesc;
697 MemoryContextSwitchTo(oldcontext);
698
699 return (Datum) 0;
700 }
701
702 /*
703 * load up the categories hash table
704 */
705 static HTAB *
load_categories_hash(char * cats_sql,MemoryContext per_query_ctx)706 load_categories_hash(char *cats_sql, MemoryContext per_query_ctx)
707 {
708 HTAB *crosstab_hash;
709 HASHCTL ctl;
710 int ret;
711 uint64 proc;
712 MemoryContext SPIcontext;
713
714 /* initialize the category hash table */
715 MemSet(&ctl, 0, sizeof(ctl));
716 ctl.keysize = MAX_CATNAME_LEN;
717 ctl.entrysize = sizeof(crosstab_HashEnt);
718 ctl.hcxt = per_query_ctx;
719
720 /*
721 * use INIT_CATS, defined above as a guess of how many hash table entries
722 * to create, initially
723 */
724 crosstab_hash = hash_create("crosstab hash",
725 INIT_CATS,
726 &ctl,
727 HASH_ELEM | HASH_CONTEXT);
728
729 /* Connect to SPI manager */
730 if ((ret = SPI_connect()) < 0)
731 /* internal error */
732 elog(ERROR, "load_categories_hash: SPI_connect returned %d", ret);
733
734 /* Retrieve the category name rows */
735 ret = SPI_execute(cats_sql, true, 0);
736 proc = SPI_processed;
737
738 /* Check for qualifying tuples */
739 if ((ret == SPI_OK_SELECT) && (proc > 0))
740 {
741 SPITupleTable *spi_tuptable = SPI_tuptable;
742 TupleDesc spi_tupdesc = spi_tuptable->tupdesc;
743 uint64 i;
744
745 /*
746 * The provided categories SQL query must always return one column:
747 * category - the label or identifier for each column
748 */
749 if (spi_tupdesc->natts != 1)
750 ereport(ERROR,
751 (errcode(ERRCODE_SYNTAX_ERROR),
752 errmsg("provided \"categories\" SQL must " \
753 "return 1 column of at least one row")));
754
755 for (i = 0; i < proc; i++)
756 {
757 crosstab_cat_desc *catdesc;
758 char *catname;
759 HeapTuple spi_tuple;
760
761 /* get the next sql result tuple */
762 spi_tuple = spi_tuptable->vals[i];
763
764 /* get the category from the current sql result tuple */
765 catname = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
766 if (catname == NULL)
767 ereport(ERROR,
768 (errcode(ERRCODE_SYNTAX_ERROR),
769 errmsg("provided \"categories\" SQL must " \
770 "not return NULL values")));
771
772 SPIcontext = MemoryContextSwitchTo(per_query_ctx);
773
774 catdesc = (crosstab_cat_desc *) palloc(sizeof(crosstab_cat_desc));
775 catdesc->catname = catname;
776 catdesc->attidx = i;
777
778 /* Add the proc description block to the hashtable */
779 crosstab_HashTableInsert(crosstab_hash, catdesc);
780
781 MemoryContextSwitchTo(SPIcontext);
782 }
783 }
784
785 if (SPI_finish() != SPI_OK_FINISH)
786 /* internal error */
787 elog(ERROR, "load_categories_hash: SPI_finish() failed");
788
789 return crosstab_hash;
790 }
791
792 /*
793 * create and populate the crosstab tuplestore using the provided source query
794 */
795 static Tuplestorestate *
get_crosstab_tuplestore(char * sql,HTAB * crosstab_hash,TupleDesc tupdesc,MemoryContext per_query_ctx,bool randomAccess)796 get_crosstab_tuplestore(char *sql,
797 HTAB *crosstab_hash,
798 TupleDesc tupdesc,
799 MemoryContext per_query_ctx,
800 bool randomAccess)
801 {
802 Tuplestorestate *tupstore;
803 int num_categories = hash_get_num_entries(crosstab_hash);
804 AttInMetadata *attinmeta = TupleDescGetAttInMetadata(tupdesc);
805 char **values;
806 HeapTuple tuple;
807 int ret;
808 uint64 proc;
809
810 /* initialize our tuplestore (while still in query context!) */
811 tupstore = tuplestore_begin_heap(randomAccess, false, work_mem);
812
813 /* Connect to SPI manager */
814 if ((ret = SPI_connect()) < 0)
815 /* internal error */
816 elog(ERROR, "get_crosstab_tuplestore: SPI_connect returned %d", ret);
817
818 /* Now retrieve the crosstab source rows */
819 ret = SPI_execute(sql, true, 0);
820 proc = SPI_processed;
821
822 /* Check for qualifying tuples */
823 if ((ret == SPI_OK_SELECT) && (proc > 0))
824 {
825 SPITupleTable *spi_tuptable = SPI_tuptable;
826 TupleDesc spi_tupdesc = spi_tuptable->tupdesc;
827 int ncols = spi_tupdesc->natts;
828 char *rowid;
829 char *lastrowid = NULL;
830 bool firstpass = true;
831 uint64 i;
832 int j;
833 int result_ncols;
834
835 if (num_categories == 0)
836 {
837 /* no qualifying category tuples */
838 ereport(ERROR,
839 (errcode(ERRCODE_SYNTAX_ERROR),
840 errmsg("provided \"categories\" SQL must " \
841 "return 1 column of at least one row")));
842 }
843
844 /*
845 * The provided SQL query must always return at least three columns:
846 *
847 * 1. rowname the label for each row - column 1 in the final result
848 * 2. category the label for each value-column in the final result 3.
849 * value the values used to populate the value-columns
850 *
851 * If there are more than three columns, the last two are taken as
852 * "category" and "values". The first column is taken as "rowname".
853 * Additional columns (2 thru N-2) are assumed the same for the same
854 * "rowname", and are copied into the result tuple from the first time
855 * we encounter a particular rowname.
856 */
857 if (ncols < 3)
858 ereport(ERROR,
859 (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
860 errmsg("invalid source data SQL statement"),
861 errdetail("The provided SQL must return 3 " \
862 " columns; rowid, category, and values.")));
863
864 result_ncols = (ncols - 2) + num_categories;
865
866 /* Recheck to make sure we tuple descriptor still looks reasonable */
867 if (tupdesc->natts != result_ncols)
868 ereport(ERROR,
869 (errcode(ERRCODE_SYNTAX_ERROR),
870 errmsg("invalid return type"),
871 errdetail("Query-specified return " \
872 "tuple has %d columns but crosstab " \
873 "returns %d.", tupdesc->natts, result_ncols)));
874
875 /* allocate space and make sure it's clear */
876 values = (char **) palloc0(result_ncols * sizeof(char *));
877
878 for (i = 0; i < proc; i++)
879 {
880 HeapTuple spi_tuple;
881 crosstab_cat_desc *catdesc;
882 char *catname;
883
884 /* get the next sql result tuple */
885 spi_tuple = spi_tuptable->vals[i];
886
887 /* get the rowid from the current sql result tuple */
888 rowid = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
889
890 /*
891 * if we're on a new output row, grab the column values up to
892 * column N-2 now
893 */
894 if (firstpass || !xstreq(lastrowid, rowid))
895 {
896 /*
897 * a new row means we need to flush the old one first, unless
898 * we're on the very first row
899 */
900 if (!firstpass)
901 {
902 /* rowid changed, flush the previous output row */
903 tuple = BuildTupleFromCStrings(attinmeta, values);
904
905 tuplestore_puttuple(tupstore, tuple);
906
907 for (j = 0; j < result_ncols; j++)
908 xpfree(values[j]);
909 }
910
911 values[0] = rowid;
912 for (j = 1; j < ncols - 2; j++)
913 values[j] = SPI_getvalue(spi_tuple, spi_tupdesc, j + 1);
914
915 /* we're no longer on the first pass */
916 firstpass = false;
917 }
918
919 /* look up the category and fill in the appropriate column */
920 catname = SPI_getvalue(spi_tuple, spi_tupdesc, ncols - 1);
921
922 if (catname != NULL)
923 {
924 crosstab_HashTableLookup(crosstab_hash, catname, catdesc);
925
926 if (catdesc)
927 values[catdesc->attidx + ncols - 2] =
928 SPI_getvalue(spi_tuple, spi_tupdesc, ncols);
929 }
930
931 xpfree(lastrowid);
932 xpstrdup(lastrowid, rowid);
933 }
934
935 /* flush the last output row */
936 tuple = BuildTupleFromCStrings(attinmeta, values);
937
938 tuplestore_puttuple(tupstore, tuple);
939 }
940
941 if (SPI_finish() != SPI_OK_FINISH)
942 /* internal error */
943 elog(ERROR, "get_crosstab_tuplestore: SPI_finish() failed");
944
945 tuplestore_donestoring(tupstore);
946
947 return tupstore;
948 }
949
950 /*
951 * connectby_text - produce a result set from a hierarchical (parent/child)
952 * table.
953 *
954 * e.g. given table foo:
955 *
956 * keyid parent_keyid pos
957 * ------+------------+--
958 * row1 NULL 0
959 * row2 row1 0
960 * row3 row1 0
961 * row4 row2 1
962 * row5 row2 0
963 * row6 row4 0
964 * row7 row3 0
965 * row8 row6 0
966 * row9 row5 0
967 *
968 *
969 * connectby(text relname, text keyid_fld, text parent_keyid_fld
970 * [, text orderby_fld], text start_with, int max_depth
971 * [, text branch_delim])
972 * connectby('foo', 'keyid', 'parent_keyid', 'pos', 'row2', 0, '~') returns:
973 *
974 * keyid parent_id level branch serial
975 * ------+-----------+--------+-----------------------
976 * row2 NULL 0 row2 1
977 * row5 row2 1 row2~row5 2
978 * row9 row5 2 row2~row5~row9 3
979 * row4 row2 1 row2~row4 4
980 * row6 row4 2 row2~row4~row6 5
981 * row8 row6 3 row2~row4~row6~row8 6
982 *
983 */
984 PG_FUNCTION_INFO_V1(connectby_text);
985
986 #define CONNECTBY_NCOLS 4
987 #define CONNECTBY_NCOLS_NOBRANCH 3
988
989 Datum
connectby_text(PG_FUNCTION_ARGS)990 connectby_text(PG_FUNCTION_ARGS)
991 {
992 char *relname = text_to_cstring(PG_GETARG_TEXT_PP(0));
993 char *key_fld = text_to_cstring(PG_GETARG_TEXT_PP(1));
994 char *parent_key_fld = text_to_cstring(PG_GETARG_TEXT_PP(2));
995 char *start_with = text_to_cstring(PG_GETARG_TEXT_PP(3));
996 int max_depth = PG_GETARG_INT32(4);
997 char *branch_delim = NULL;
998 bool show_branch = false;
999 bool show_serial = false;
1000 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
1001 TupleDesc tupdesc;
1002 AttInMetadata *attinmeta;
1003 MemoryContext per_query_ctx;
1004 MemoryContext oldcontext;
1005
1006 /* check to see if caller supports us returning a tuplestore */
1007 if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
1008 ereport(ERROR,
1009 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1010 errmsg("set-valued function called in context that cannot accept a set")));
1011 if (!(rsinfo->allowedModes & SFRM_Materialize) ||
1012 rsinfo->expectedDesc == NULL)
1013 ereport(ERROR,
1014 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1015 errmsg("materialize mode required, but it is not " \
1016 "allowed in this context")));
1017
1018 if (fcinfo->nargs == 6)
1019 {
1020 branch_delim = text_to_cstring(PG_GETARG_TEXT_PP(5));
1021 show_branch = true;
1022 }
1023 else
1024 /* default is no show, tilde for the delimiter */
1025 branch_delim = pstrdup("~");
1026
1027 per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
1028 oldcontext = MemoryContextSwitchTo(per_query_ctx);
1029
1030 /* get the requested return tuple description */
1031 tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
1032
1033 /* does it meet our needs */
1034 validateConnectbyTupleDesc(tupdesc, show_branch, show_serial);
1035
1036 /* OK, use it then */
1037 attinmeta = TupleDescGetAttInMetadata(tupdesc);
1038
1039 /* OK, go to work */
1040 rsinfo->returnMode = SFRM_Materialize;
1041 rsinfo->setResult = connectby(relname,
1042 key_fld,
1043 parent_key_fld,
1044 NULL,
1045 branch_delim,
1046 start_with,
1047 max_depth,
1048 show_branch,
1049 show_serial,
1050 per_query_ctx,
1051 rsinfo->allowedModes & SFRM_Materialize_Random,
1052 attinmeta);
1053 rsinfo->setDesc = tupdesc;
1054
1055 MemoryContextSwitchTo(oldcontext);
1056
1057 /*
1058 * SFRM_Materialize mode expects us to return a NULL Datum. The actual
1059 * tuples are in our tuplestore and passed back through rsinfo->setResult.
1060 * rsinfo->setDesc is set to the tuple description that we actually used
1061 * to build our tuples with, so the caller can verify we did what it was
1062 * expecting.
1063 */
1064 return (Datum) 0;
1065 }
1066
1067 PG_FUNCTION_INFO_V1(connectby_text_serial);
1068 Datum
connectby_text_serial(PG_FUNCTION_ARGS)1069 connectby_text_serial(PG_FUNCTION_ARGS)
1070 {
1071 char *relname = text_to_cstring(PG_GETARG_TEXT_PP(0));
1072 char *key_fld = text_to_cstring(PG_GETARG_TEXT_PP(1));
1073 char *parent_key_fld = text_to_cstring(PG_GETARG_TEXT_PP(2));
1074 char *orderby_fld = text_to_cstring(PG_GETARG_TEXT_PP(3));
1075 char *start_with = text_to_cstring(PG_GETARG_TEXT_PP(4));
1076 int max_depth = PG_GETARG_INT32(5);
1077 char *branch_delim = NULL;
1078 bool show_branch = false;
1079 bool show_serial = true;
1080 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
1081 TupleDesc tupdesc;
1082 AttInMetadata *attinmeta;
1083 MemoryContext per_query_ctx;
1084 MemoryContext oldcontext;
1085
1086 /* check to see if caller supports us returning a tuplestore */
1087 if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
1088 ereport(ERROR,
1089 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1090 errmsg("set-valued function called in context that cannot accept a set")));
1091 if (!(rsinfo->allowedModes & SFRM_Materialize) ||
1092 rsinfo->expectedDesc == NULL)
1093 ereport(ERROR,
1094 (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
1095 errmsg("materialize mode required, but it is not " \
1096 "allowed in this context")));
1097
1098 if (fcinfo->nargs == 7)
1099 {
1100 branch_delim = text_to_cstring(PG_GETARG_TEXT_PP(6));
1101 show_branch = true;
1102 }
1103 else
1104 /* default is no show, tilde for the delimiter */
1105 branch_delim = pstrdup("~");
1106
1107 per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
1108 oldcontext = MemoryContextSwitchTo(per_query_ctx);
1109
1110 /* get the requested return tuple description */
1111 tupdesc = CreateTupleDescCopy(rsinfo->expectedDesc);
1112
1113 /* does it meet our needs */
1114 validateConnectbyTupleDesc(tupdesc, show_branch, show_serial);
1115
1116 /* OK, use it then */
1117 attinmeta = TupleDescGetAttInMetadata(tupdesc);
1118
1119 /* OK, go to work */
1120 rsinfo->returnMode = SFRM_Materialize;
1121 rsinfo->setResult = connectby(relname,
1122 key_fld,
1123 parent_key_fld,
1124 orderby_fld,
1125 branch_delim,
1126 start_with,
1127 max_depth,
1128 show_branch,
1129 show_serial,
1130 per_query_ctx,
1131 rsinfo->allowedModes & SFRM_Materialize_Random,
1132 attinmeta);
1133 rsinfo->setDesc = tupdesc;
1134
1135 MemoryContextSwitchTo(oldcontext);
1136
1137 /*
1138 * SFRM_Materialize mode expects us to return a NULL Datum. The actual
1139 * tuples are in our tuplestore and passed back through rsinfo->setResult.
1140 * rsinfo->setDesc is set to the tuple description that we actually used
1141 * to build our tuples with, so the caller can verify we did what it was
1142 * expecting.
1143 */
1144 return (Datum) 0;
1145 }
1146
1147
1148 /*
1149 * connectby - does the real work for connectby_text()
1150 */
1151 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,bool randomAccess,AttInMetadata * attinmeta)1152 connectby(char *relname,
1153 char *key_fld,
1154 char *parent_key_fld,
1155 char *orderby_fld,
1156 char *branch_delim,
1157 char *start_with,
1158 int max_depth,
1159 bool show_branch,
1160 bool show_serial,
1161 MemoryContext per_query_ctx,
1162 bool randomAccess,
1163 AttInMetadata *attinmeta)
1164 {
1165 Tuplestorestate *tupstore = NULL;
1166 int ret;
1167 MemoryContext oldcontext;
1168
1169 int serial = 1;
1170
1171 /* Connect to SPI manager */
1172 if ((ret = SPI_connect()) < 0)
1173 /* internal error */
1174 elog(ERROR, "connectby: SPI_connect returned %d", ret);
1175
1176 /* switch to longer term context to create the tuple store */
1177 oldcontext = MemoryContextSwitchTo(per_query_ctx);
1178
1179 /* initialize our tuplestore */
1180 tupstore = tuplestore_begin_heap(randomAccess, false, work_mem);
1181
1182 MemoryContextSwitchTo(oldcontext);
1183
1184 /* now go get the whole tree */
1185 build_tuplestore_recursively(key_fld,
1186 parent_key_fld,
1187 relname,
1188 orderby_fld,
1189 branch_delim,
1190 start_with,
1191 start_with, /* current_branch */
1192 0, /* initial level is 0 */
1193 &serial, /* initial serial is 1 */
1194 max_depth,
1195 show_branch,
1196 show_serial,
1197 per_query_ctx,
1198 attinmeta,
1199 tupstore);
1200
1201 SPI_finish();
1202
1203 return tupstore;
1204 }
1205
1206 static void
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)1207 build_tuplestore_recursively(char *key_fld,
1208 char *parent_key_fld,
1209 char *relname,
1210 char *orderby_fld,
1211 char *branch_delim,
1212 char *start_with,
1213 char *branch,
1214 int level,
1215 int *serial,
1216 int max_depth,
1217 bool show_branch,
1218 bool show_serial,
1219 MemoryContext per_query_ctx,
1220 AttInMetadata *attinmeta,
1221 Tuplestorestate *tupstore)
1222 {
1223 TupleDesc tupdesc = attinmeta->tupdesc;
1224 int ret;
1225 uint64 proc;
1226 int serial_column;
1227 StringInfoData sql;
1228 char **values;
1229 char *current_key;
1230 char *current_key_parent;
1231 char current_level[INT32_STRLEN];
1232 char serial_str[INT32_STRLEN];
1233 char *current_branch;
1234 HeapTuple tuple;
1235
1236 if (max_depth > 0 && level > max_depth)
1237 return;
1238
1239 initStringInfo(&sql);
1240
1241 /* Build initial sql statement */
1242 if (!show_serial)
1243 {
1244 appendStringInfo(&sql, "SELECT %s, %s FROM %s WHERE %s = %s AND %s IS NOT NULL AND %s <> %s",
1245 key_fld,
1246 parent_key_fld,
1247 relname,
1248 parent_key_fld,
1249 quote_literal_cstr(start_with),
1250 key_fld, key_fld, parent_key_fld);
1251 serial_column = 0;
1252 }
1253 else
1254 {
1255 appendStringInfo(&sql, "SELECT %s, %s FROM %s WHERE %s = %s AND %s IS NOT NULL AND %s <> %s ORDER BY %s",
1256 key_fld,
1257 parent_key_fld,
1258 relname,
1259 parent_key_fld,
1260 quote_literal_cstr(start_with),
1261 key_fld, key_fld, parent_key_fld,
1262 orderby_fld);
1263 serial_column = 1;
1264 }
1265
1266 if (show_branch)
1267 values = (char **) palloc((CONNECTBY_NCOLS + serial_column) * sizeof(char *));
1268 else
1269 values = (char **) palloc((CONNECTBY_NCOLS_NOBRANCH + serial_column) * sizeof(char *));
1270
1271 /* First time through, do a little setup */
1272 if (level == 0)
1273 {
1274 /* root value is the one we initially start with */
1275 values[0] = start_with;
1276
1277 /* root value has no parent */
1278 values[1] = NULL;
1279
1280 /* root level is 0 */
1281 sprintf(current_level, "%d", level);
1282 values[2] = current_level;
1283
1284 /* root branch is just starting root value */
1285 if (show_branch)
1286 values[3] = start_with;
1287
1288 /* root starts the serial with 1 */
1289 if (show_serial)
1290 {
1291 sprintf(serial_str, "%d", (*serial)++);
1292 if (show_branch)
1293 values[4] = serial_str;
1294 else
1295 values[3] = serial_str;
1296 }
1297
1298 /* construct the tuple */
1299 tuple = BuildTupleFromCStrings(attinmeta, values);
1300
1301 /* now store it */
1302 tuplestore_puttuple(tupstore, tuple);
1303
1304 /* increment level */
1305 level++;
1306 }
1307
1308 /* Retrieve the desired rows */
1309 ret = SPI_execute(sql.data, true, 0);
1310 proc = SPI_processed;
1311
1312 /* Check for qualifying tuples */
1313 if ((ret == SPI_OK_SELECT) && (proc > 0))
1314 {
1315 HeapTuple spi_tuple;
1316 SPITupleTable *tuptable = SPI_tuptable;
1317 TupleDesc spi_tupdesc = tuptable->tupdesc;
1318 uint64 i;
1319 StringInfoData branchstr;
1320 StringInfoData chk_branchstr;
1321 StringInfoData chk_current_key;
1322
1323 /*
1324 * Check that return tupdesc is compatible with the one we got from
1325 * the query.
1326 */
1327 compatConnectbyTupleDescs(tupdesc, spi_tupdesc);
1328
1329 initStringInfo(&branchstr);
1330 initStringInfo(&chk_branchstr);
1331 initStringInfo(&chk_current_key);
1332
1333 for (i = 0; i < proc; i++)
1334 {
1335 /* initialize branch for this pass */
1336 appendStringInfoString(&branchstr, branch);
1337 appendStringInfo(&chk_branchstr, "%s%s%s", branch_delim, branch, branch_delim);
1338
1339 /* get the next sql result tuple */
1340 spi_tuple = tuptable->vals[i];
1341
1342 /* get the current key (might be NULL) */
1343 current_key = SPI_getvalue(spi_tuple, spi_tupdesc, 1);
1344
1345 /* get the parent key (might be NULL) */
1346 current_key_parent = SPI_getvalue(spi_tuple, spi_tupdesc, 2);
1347
1348 /* get the current level */
1349 sprintf(current_level, "%d", level);
1350
1351 /* check to see if this key is also an ancestor */
1352 if (current_key)
1353 {
1354 appendStringInfo(&chk_current_key, "%s%s%s",
1355 branch_delim, current_key, branch_delim);
1356 if (strstr(chk_branchstr.data, chk_current_key.data))
1357 ereport(ERROR,
1358 (errcode(ERRCODE_INVALID_RECURSION),
1359 errmsg("infinite recursion detected")));
1360 }
1361
1362 /* OK, extend the branch */
1363 if (current_key)
1364 appendStringInfo(&branchstr, "%s%s", branch_delim, current_key);
1365 current_branch = branchstr.data;
1366
1367 /* build a tuple */
1368 values[0] = current_key;
1369 values[1] = current_key_parent;
1370 values[2] = current_level;
1371 if (show_branch)
1372 values[3] = current_branch;
1373 if (show_serial)
1374 {
1375 sprintf(serial_str, "%d", (*serial)++);
1376 if (show_branch)
1377 values[4] = serial_str;
1378 else
1379 values[3] = serial_str;
1380 }
1381
1382 tuple = BuildTupleFromCStrings(attinmeta, values);
1383
1384 /* store the tuple for later use */
1385 tuplestore_puttuple(tupstore, tuple);
1386
1387 heap_freetuple(tuple);
1388
1389 /* recurse using current_key as the new start_with */
1390 if (current_key)
1391 build_tuplestore_recursively(key_fld,
1392 parent_key_fld,
1393 relname,
1394 orderby_fld,
1395 branch_delim,
1396 current_key,
1397 current_branch,
1398 level + 1,
1399 serial,
1400 max_depth,
1401 show_branch,
1402 show_serial,
1403 per_query_ctx,
1404 attinmeta,
1405 tupstore);
1406
1407 xpfree(current_key);
1408 xpfree(current_key_parent);
1409
1410 /* reset branch for next pass */
1411 resetStringInfo(&branchstr);
1412 resetStringInfo(&chk_branchstr);
1413 resetStringInfo(&chk_current_key);
1414 }
1415
1416 xpfree(branchstr.data);
1417 xpfree(chk_branchstr.data);
1418 xpfree(chk_current_key.data);
1419 }
1420 }
1421
1422 /*
1423 * Check expected (query runtime) tupdesc suitable for Connectby
1424 */
1425 static void
validateConnectbyTupleDesc(TupleDesc td,bool show_branch,bool show_serial)1426 validateConnectbyTupleDesc(TupleDesc td, bool show_branch, bool show_serial)
1427 {
1428 int serial_column = 0;
1429
1430 if (show_serial)
1431 serial_column = 1;
1432
1433 /* are there the correct number of columns */
1434 if (show_branch)
1435 {
1436 if (td->natts != (CONNECTBY_NCOLS + serial_column))
1437 ereport(ERROR,
1438 (errcode(ERRCODE_DATATYPE_MISMATCH),
1439 errmsg("invalid return type"),
1440 errdetail("Query-specified return tuple has " \
1441 "wrong number of columns.")));
1442 }
1443 else
1444 {
1445 if (td->natts != CONNECTBY_NCOLS_NOBRANCH + serial_column)
1446 ereport(ERROR,
1447 (errcode(ERRCODE_DATATYPE_MISMATCH),
1448 errmsg("invalid return type"),
1449 errdetail("Query-specified return tuple has " \
1450 "wrong number of columns.")));
1451 }
1452
1453 /* check that the types of the first two columns match */
1454 if (TupleDescAttr(td, 0)->atttypid != TupleDescAttr(td, 1)->atttypid)
1455 ereport(ERROR,
1456 (errcode(ERRCODE_DATATYPE_MISMATCH),
1457 errmsg("invalid return type"),
1458 errdetail("First two columns must be the same type.")));
1459
1460 /* check that the type of the third column is INT4 */
1461 if (TupleDescAttr(td, 2)->atttypid != INT4OID)
1462 ereport(ERROR,
1463 (errcode(ERRCODE_DATATYPE_MISMATCH),
1464 errmsg("invalid return type"),
1465 errdetail("Third column must be type %s.",
1466 format_type_be(INT4OID))));
1467
1468 /* check that the type of the fourth column is TEXT if applicable */
1469 if (show_branch && TupleDescAttr(td, 3)->atttypid != TEXTOID)
1470 ereport(ERROR,
1471 (errcode(ERRCODE_DATATYPE_MISMATCH),
1472 errmsg("invalid return type"),
1473 errdetail("Fourth column must be type %s.",
1474 format_type_be(TEXTOID))));
1475
1476 /* check that the type of the fifth column is INT4 */
1477 if (show_branch && show_serial &&
1478 TupleDescAttr(td, 4)->atttypid != INT4OID)
1479 ereport(ERROR,
1480 (errcode(ERRCODE_DATATYPE_MISMATCH),
1481 errmsg("query-specified return tuple not valid for Connectby: "
1482 "fifth column must be type %s",
1483 format_type_be(INT4OID))));
1484
1485 /* check that the type of the fifth column is INT4 */
1486 if (!show_branch && show_serial &&
1487 TupleDescAttr(td, 3)->atttypid != INT4OID)
1488 ereport(ERROR,
1489 (errcode(ERRCODE_DATATYPE_MISMATCH),
1490 errmsg("query-specified return tuple not valid for Connectby: "
1491 "fourth column must be type %s",
1492 format_type_be(INT4OID))));
1493
1494 /* OK, the tupdesc is valid for our purposes */
1495 }
1496
1497 /*
1498 * Check if spi sql tupdesc and return tupdesc are compatible
1499 */
1500 static void
compatConnectbyTupleDescs(TupleDesc ret_tupdesc,TupleDesc sql_tupdesc)1501 compatConnectbyTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
1502 {
1503 Oid ret_atttypid;
1504 Oid sql_atttypid;
1505 int32 ret_atttypmod;
1506 int32 sql_atttypmod;
1507
1508 /*
1509 * Result must have at least 2 columns.
1510 */
1511 if (sql_tupdesc->natts < 2)
1512 ereport(ERROR,
1513 (errcode(ERRCODE_DATATYPE_MISMATCH),
1514 errmsg("invalid return type"),
1515 errdetail("Query must return at least two columns.")));
1516
1517 /*
1518 * These columns must match the result type indicated by the calling
1519 * query.
1520 */
1521 ret_atttypid = TupleDescAttr(ret_tupdesc, 0)->atttypid;
1522 sql_atttypid = TupleDescAttr(sql_tupdesc, 0)->atttypid;
1523 ret_atttypmod = TupleDescAttr(ret_tupdesc, 0)->atttypmod;
1524 sql_atttypmod = TupleDescAttr(sql_tupdesc, 0)->atttypmod;
1525 if (ret_atttypid != sql_atttypid ||
1526 (ret_atttypmod >= 0 && ret_atttypmod != sql_atttypmod))
1527 ereport(ERROR,
1528 (errcode(ERRCODE_DATATYPE_MISMATCH),
1529 errmsg("invalid return type"),
1530 errdetail("SQL key field type %s does " \
1531 "not match return key field type %s.",
1532 format_type_with_typemod(ret_atttypid, ret_atttypmod),
1533 format_type_with_typemod(sql_atttypid, sql_atttypmod))));
1534
1535 ret_atttypid = TupleDescAttr(ret_tupdesc, 1)->atttypid;
1536 sql_atttypid = TupleDescAttr(sql_tupdesc, 1)->atttypid;
1537 ret_atttypmod = TupleDescAttr(ret_tupdesc, 1)->atttypmod;
1538 sql_atttypmod = TupleDescAttr(sql_tupdesc, 1)->atttypmod;
1539 if (ret_atttypid != sql_atttypid ||
1540 (ret_atttypmod >= 0 && ret_atttypmod != sql_atttypmod))
1541 ereport(ERROR,
1542 (errcode(ERRCODE_DATATYPE_MISMATCH),
1543 errmsg("invalid return type"),
1544 errdetail("SQL parent key field type %s does " \
1545 "not match return parent key field type %s.",
1546 format_type_with_typemod(ret_atttypid, ret_atttypmod),
1547 format_type_with_typemod(sql_atttypid, sql_atttypmod))));
1548
1549 /* OK, the two tupdescs are compatible for our purposes */
1550 }
1551
1552 /*
1553 * Check if two tupdescs match in type of attributes
1554 */
1555 static bool
compatCrosstabTupleDescs(TupleDesc ret_tupdesc,TupleDesc sql_tupdesc)1556 compatCrosstabTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
1557 {
1558 int i;
1559 Form_pg_attribute ret_attr;
1560 Oid ret_atttypid;
1561 Form_pg_attribute sql_attr;
1562 Oid sql_atttypid;
1563
1564 if (ret_tupdesc->natts < 2 ||
1565 sql_tupdesc->natts < 3)
1566 return false;
1567
1568 /* check the rowid types match */
1569 ret_atttypid = TupleDescAttr(ret_tupdesc, 0)->atttypid;
1570 sql_atttypid = TupleDescAttr(sql_tupdesc, 0)->atttypid;
1571 if (ret_atttypid != sql_atttypid)
1572 ereport(ERROR,
1573 (errcode(ERRCODE_DATATYPE_MISMATCH),
1574 errmsg("invalid return type"),
1575 errdetail("SQL rowid datatype does not match " \
1576 "return rowid datatype.")));
1577
1578 /*
1579 * - attribute [1] of the sql tuple is the category; no need to check it -
1580 * attribute [2] of the sql tuple should match attributes [1] to [natts]
1581 * of the return tuple
1582 */
1583 sql_attr = TupleDescAttr(sql_tupdesc, 2);
1584 for (i = 1; i < ret_tupdesc->natts; i++)
1585 {
1586 ret_attr = TupleDescAttr(ret_tupdesc, i);
1587
1588 if (ret_attr->atttypid != sql_attr->atttypid)
1589 return false;
1590 }
1591
1592 /* OK, the two tupdescs are compatible for our purposes */
1593 return true;
1594 }
1595