From: drh Date: Mon, 31 Mar 2014 19:49:00 +0000 (+0000) Subject: Also make sure an index that is a proper subset of some other index has a X-Git-Tag: version-3.8.5~83^2~1 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3fb183d2f7f83cdc9cb406dccbe97d731f1e0644;p=thirdparty%2Fsqlite.git Also make sure an index that is a proper subset of some other index has a higher cost than that other index. Add test cases. FossilOrigin-Name: b7830d232b073a197aa1092e78cb24e88cb10fd3 --- diff --git a/manifest b/manifest index ac1faf182f..7824fe6caa 100644 --- a/manifest +++ b/manifest @@ -1,5 +1,5 @@ -C Make\ssure\sthat\san\sindex\sthat\scovers\sa\sproper\ssuperset\sof\sthe\sWHERE\sclause\nterms\sof\ssome\sother\sindex\shas\sa\slower\scost\sthan\sthe\sother\sindex. -D 2014-03-31T18:24:18.867 +C Also\smake\ssure\san\sindex\sthat\sis\sa\sproper\ssubset\sof\ssome\sother\sindex\shas\sa\nhigher\scost\sthan\sthat\sother\sindex.\s\sAdd\stest\scases. +D 2014-03-31T19:49:00.374 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f F Makefile.in 2ef13430cd359f7b361bb863504e227b25cc7f81 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23 @@ -291,7 +291,7 @@ F src/vtab.c 21b932841e51ebd7d075e2d0ad1415dce8d2d5fd F src/wal.c 76e7fc6de229bea8b30bb2539110f03a494dc3a8 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4 F src/walker.c 11edb74d587bc87b33ca96a5173e3ec1b8389e45 -F src/where.c 50ac3154473b5c8df15c7b8dbd19da385fa859e1 +F src/where.c 182f16d91060418dfcc7401d24e43d8ec24e026c F src/whereInt.h 2564055b440e44ebec8b47f237bbccae6719b7af F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2 @@ -1093,6 +1093,7 @@ F test/whereD.test 6c2feb79ef1f68381b07f39017fe5f9b96da8d62 F test/whereE.test b3a055eef928c992b0a33198a7b8dc10eea5ad2f F test/whereF.test 5b2ba0dbe8074aa13e416b37c753991f0a2492d7 F test/whereG.test eb3a46b3eaf38e25e3013433b2db8a25a866c215 +F test/whereH.test e4b07f7a3c2f5d31195cd33710054c78667573b2 F test/wherelimit.test 5e9fd41e79bb2b2d588ed999d641d9c965619b31 F test/wild001.test bca33f499866f04c24510d74baf1e578d4e44b1c F test/win32heap.test ea19770974795cff26e11575e12d422dbd16893c @@ -1159,7 +1160,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4 F tool/warnings.sh d1a6de74685f360ab718efda6265994b99bbea01 F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff -P 8f869ca7a6eaa9ca7a08102290e6c606735f9090 -R 76b8d8088ba83ec014dc8bf476fa6749 +P ea8b0910040198751551b0b960e6b783913607df +R 176e1ff66c14893be5de17b3890f1972 U drh -Z ecebe13d1c9f7ea1da970c5f6118dc52 +Z 3bf4657410567331f2f5534ba4eae60e diff --git a/manifest.uuid b/manifest.uuid index 649fc9530b..a0ffd4b3db 100644 --- a/manifest.uuid +++ b/manifest.uuid @@ -1 +1 @@ -ea8b0910040198751551b0b960e6b783913607df \ No newline at end of file +b7830d232b073a197aa1092e78cb24e88cb10fd3 \ No newline at end of file diff --git a/src/where.c b/src/where.c index 38c3712977..9882b4873f 100644 --- a/src/where.c +++ b/src/where.c @@ -3712,46 +3712,54 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){ } /* -** Compare every WhereLoop X on the list p against pTemplate. If: -** -** (1) both X and pTemplate refer to the same table, and -** (2) both X and pTemplate use a single index, and -** (3) pTemplate uses all the same WHERE clause terms as X plus -** at least one more term, +** Return TRUE if the set of WHERE clause terms used by pA is a proper +** subset of the WHERE clause terms used by pB. +*/ +static int whereLoopProperSubset(const WhereLoop *pA, const WhereLoop *pB){ + int i, j; + if( pA->nLTerm>=pB->nLTerm ) return 0; + for(j=0, i=pA->nLTerm-1; i>=0 && j>=0; i--){ + for(j=pB->nLTerm-1; j>=0; j--){ + if( pB->aLTerm[j]==pA->aLTerm[i] ) break; + } + } + return j>=0; +} + +/* +** Try to adjust the cost of WhereLoop pTemplate upwards or downwards so +** that: ** -** then make sure the cost pTemplate is less than the cost of X, adjusting -** the cost of pTemplate downward if necessary. +** (1) pTemplate costs less than any other WhereLoops that are a proper +** subset of pTemplate ** -** Example: When computing the query plan for the SELECT below: +** (2) pTemplate costs more than any other WhereLoops for which pTemplate +** is a proper subset. ** -** CREATE TABLE t1(a,b,c,d); -** CREATE INDEX t1abc ON t1(a,b,c); -** CREATE INDEX t1bc ON t1(b,c); -** SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c; -** -** Make sure the cost of using three three columns of index t1abc is less -** than the cost of using both columns of t1bc. +** To say "WhereLoop X is a proper subset of Y" means that X uses fewer +** WHERE clause terms than Y and that every WHERE clause term used by X is +** also used by Y. */ static void whereLoopAdjustCost(const WhereLoop *p, WhereLoop *pTemplate){ if( (pTemplate->wsFlags & WHERE_INDEXED)==0 ) return; - if( pTemplate->nLTerm==0 ) return; for(; p; p=p->pNextLoop){ - if( p->iTab==pTemplate->iTab - && (p->wsFlags & WHERE_INDEXED)!=0 - && p->nLTermnLTerm + if( p->iTab!=pTemplate->iTab ) continue; + if( (p->wsFlags & WHERE_INDEXED)==0 ) continue; + if( p->nLTermnLTerm && (p->rRunrRun || (p->rRun==pTemplate->rRun && p->nOut<=pTemplate->nOut)) + && whereLoopProperSubset(p, pTemplate) ){ - int i, j; - for(j=0, i=p->nLTerm-1; i>=0 && j>=0; i--){ - for(j=pTemplate->nLTerm-1; j>=0; j--){ - if( pTemplate->aLTerm[j]==p->aLTerm[i] ) break; - } - } - if( j>=0 ){ - pTemplate->rRun = p->rRun; - pTemplate->nOut = p->nOut - 1; - } + pTemplate->rRun = p->rRun; + pTemplate->nOut = p->nOut - 1; + }else + if( p->nLTerm>pTemplate->nLTerm + && (p->rRun>pTemplate->rRun || (p->rRun==pTemplate->rRun && + p->nOut>=pTemplate->nOut)) + && whereLoopProperSubset(pTemplate, p) + ){ + pTemplate->rRun = p->rRun; + pTemplate->nOut = p->nOut + 1; } } } diff --git a/test/whereH.test b/test/whereH.test new file mode 100644 index 0000000000..c252fe1ef7 --- /dev/null +++ b/test/whereH.test @@ -0,0 +1,139 @@ +# 2014-03-31 +# +# The author disclaims copyright to this source code. In place of +# a legal notice, here is a blessing: +# +# May you do good and not evil. +# May you find forgiveness for yourself and forgive others. +# May you share freely, never taking more than you give. +# +#*********************************************************************** +# +# Test cases for query planning decisions where one candidate index +# covers a proper superset of the WHERE clause terms of another +# candidate index. +# + +set testdir [file dirname $argv0] +source $testdir/tester.tcl + +do_execsql_test whereH-1.1 { + CREATE TABLE t1(a,b,c,d); + CREATE INDEX t1abc ON t1(a,b,c); + CREATE INDEX t1bc ON t1(b,c); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c; +} {/INDEX t1abc /} +do_execsql_test whereH-1.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-2.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d); + CREATE INDEX t1bc ON t1(b,c); + CREATE INDEX t1abc ON t1(a,b,c); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c; +} {/INDEX t1abc /} +do_execsql_test whereH-2.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-3.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d,e); + CREATE INDEX t1cd ON t1(c,d); + CREATE INDEX t1bcd ON t1(b,c,d); + CREATE INDEX t1abcd ON t1(a,b,c,d); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {/INDEX t1abcd /} +do_execsql_test whereH-3.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-4.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d,e); + CREATE INDEX t1cd ON t1(c,d); + CREATE INDEX t1abcd ON t1(a,b,c,d); + CREATE INDEX t1bcd ON t1(b,c,d); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {/INDEX t1abcd /} +do_execsql_test whereH-4.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-5.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d,e); + CREATE INDEX t1bcd ON t1(b,c,d); + CREATE INDEX t1cd ON t1(c,d); + CREATE INDEX t1abcd ON t1(a,b,c,d); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {/INDEX t1abcd /} +do_execsql_test whereH-5.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-6.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d,e); + CREATE INDEX t1bcd ON t1(b,c,d); + CREATE INDEX t1abcd ON t1(a,b,c,d); + CREATE INDEX t1cd ON t1(c,d); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {/INDEX t1abcd /} +do_execsql_test whereH-6.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-7.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d,e); + CREATE INDEX t1abcd ON t1(a,b,c,d); + CREATE INDEX t1bcd ON t1(b,c,d); + CREATE INDEX t1cd ON t1(c,d); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {/INDEX t1abcd /} +do_execsql_test whereH-7.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {~/TEMP B-TREE FOR ORDER BY/} + +do_execsql_test whereH-8.1 { + DROP TABLE t1; + CREATE TABLE t1(a,b,c,d,e); + CREATE INDEX t1abcd ON t1(a,b,c,d); + CREATE INDEX t1cd ON t1(c,d); + CREATE INDEX t1bcd ON t1(b,c,d); + + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {/INDEX t1abcd /} +do_execsql_test whereH-8.2 { + EXPLAIN QUERY PLAN + SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d; +} {~/TEMP B-TREE FOR ORDER BY/} + + + +finish_test