Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Fix a segfault introduced by the row-value enhancement that comes up on a skip-scan where the first term of the index is unconstrained and the second term is of the form "columm IN (SELECT...)". |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
2401ea5acfeee8042489d1db38036ff8 |
| User & Date: | drh 2016-09-19 11:00:42 |
Context
|
2016-09-19
| ||
| 23:39 | Very small optimization in the bytecode engine. check-in: 46002511 user: drh tags: trunk | |
| 11:00 | Fix a segfault introduced by the row-value enhancement that comes up on a skip-scan where the first term of the index is unconstrained and the second term is of the form "columm IN (SELECT...)". check-in: 2401ea5a user: drh tags: trunk | |
| 10:24 | Improved performance in sqlite3ExprCodeTarget(). check-in: 75146165 user: drh tags: trunk | |
Changes
Changes to src/where.c.
2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 |
/* The expression may actually be of the form (x, y) IN (SELECT...).
** In this case there is a separate term for each of (x) and (y).
** However, the nIn multiplier should only be applied once, not once
** for each such term. The following loop checks that pTerm is the
** first such term in use, and sets nIn back to 0 if it is not. */
for(i=0; i<pNew->nLTerm-1; i++){
if( pNew->aLTerm[i]->pExpr==pExpr ) nIn = 0;
}
}else if( ALWAYS(pExpr->x.pList && pExpr->x.pList->nExpr) ){
/* "x IN (value, value, ...)" */
nIn = sqlite3LogEst(pExpr->x.pList->nExpr);
assert( nIn>0 ); /* RHS always has 2 or more terms... The parser
** changes "x IN (?)" into "x=?". */
}
|
| |
2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 |
/* The expression may actually be of the form (x, y) IN (SELECT...).
** In this case there is a separate term for each of (x) and (y).
** However, the nIn multiplier should only be applied once, not once
** for each such term. The following loop checks that pTerm is the
** first such term in use, and sets nIn back to 0 if it is not. */
for(i=0; i<pNew->nLTerm-1; i++){
if( pNew->aLTerm[i] && pNew->aLTerm[i]->pExpr==pExpr ) nIn = 0;
}
}else if( ALWAYS(pExpr->x.pList && pExpr->x.pList->nExpr) ){
/* "x IN (value, value, ...)" */
nIn = sqlite3LogEst(pExpr->x.pList->nExpr);
assert( nIn>0 ); /* RHS always has 2 or more terms... The parser
** changes "x IN (?)" into "x=?". */
}
|
Changes to test/skipscan1.test.
317 318 319 320 321 322 323 324 325 |
OR (y = 'EF' AND x = 5);
} {/ANY/}
do_execsql_test skipscan1-8.2 {
SELECT * FROM t1
WHERE y = 'AB' OR (y = 'CD' AND x = 2)
ORDER BY +x;
} {1 AB 2 CD}
finish_test
|
> > > > > > > > > > > > > > > |
317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 |
OR (y = 'EF' AND x = 5);
} {/ANY/}
do_execsql_test skipscan1-8.2 {
SELECT * FROM t1
WHERE y = 'AB' OR (y = 'CD' AND x = 2)
ORDER BY +x;
} {1 AB 2 CD}
# Segfault reported on the mailing list by Keith Medcalf on 2016-09-18.
# A skip-scan with a "column IN (SELECT ...)" on the second term of the
# index.
#
do_execsql_test skipscan1-9.2 {
CREATE TABLE t9a(a,b,c);
CREATE INDEX t9a_ab ON t9a(a,b);
CREATE TABLE t9b(x,y);
ANALYZE sqlite_master;
INSERT INTO sqlite_stat1 VALUES('t9a','t9a_ab','1000000 250000 1');
ANALYZE sqlite_master;
EXPLAIN QUERY PLAN
SELECT * FROM t9a WHERE b IN (SELECT x FROM t9b WHERE y!=5);
} {/USING INDEX t9a_ab .ANY.a. AND b=./}
finish_test
|