mirrors/sqlite
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Have the planner ensure that if one scan uses a subset of the WHERE clause of another, that scan is estimated to cost less and return fewer rows.

Browse Source 
FossilOrigin-Name: c7b34930e27597e7f634ad76be55fc436dcb84ea48d5b41b5d7f3596285dd672
This commit is contained in:
dan 2021-08-31 15:53:58 +00:00
parent beed24d57e
commit 748d8b9cdd
3 changed files with 22 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
manifest
View File

@ -1,5 +1,5 @@
C Do\snot\sdisable\sa\srowid=?\sterm\sused\sto\sdrive\san\sIPK\sindex\sif\sit\sis\sa\stransitive\sconstraint.
D 2021-08-30T17:02:48.783
C Have\sthe\splanner\sensure\sthat\sif\sone\sscan\suses\sa\ssubset\sof\sthe\sWHERE\sclause\sof\sanother,\sthat\sscan\sis\sestimated\sto\scost\sless\sand\sreturn\sfewer\srows.
D 2021-08-31T15:53:58.805
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@ -631,7 +631,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
F src/wal.c 2be08331d798237ad5d7ae0b252700ffb2b63189cb18d993496d009a93e2f81c
F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
F src/walker.c 7342becedf3f8a26f9817f08436bdf8b56ad69af83705f6b9320a0ad3092c2ac
F src/where.c 99b6e13664a7bd9a553c554978d0e253066995dade621f44cffa8928c8b493b5
F src/where.c da3981a12e9eb5a71d32bab60ac1957fd4aa337aaea07ca8019b01f8788f442a
F src/whereInt.h 9248161dd004f625ce5d3841ca9b99fed3fc8d61522cf76340fc5217dbe1375b
F src/wherecode.c 0208553a0602146b5640747c0e3f7a8c785108c2d06a160b69f23491e9dc781e
F src/whereexpr.c 3a9144a9d52e110efdc012a73b1574e7b2b4df4bf98949387cb620295eba0975
@ -1922,7 +1922,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
P 106b5e5355a3836a9756333e6dcbb13f0878a5352dab00973b8f0900879bd724
R 390ae46cb67974ab5b963609771fe7af
P 46e28cbcf6044b36aa4ddcda09adb49a46c6c6a8d41d558467ede3091304aa8c
R 7a7a4eb3153f412c9a6ad188811a1057
U dan
Z 277d9ab62dc946ab2c8cb8f1af415f95
Z 5dffd43884b54fa608822427de1e26e7

2
manifest.uuid
View File

@ -1 +1 @@
46e28cbcf6044b36aa4ddcda09adb49a46c6c6a8d41d558467ede3091304aa8c
c7b34930e27597e7f634ad76be55fc436dcb84ea48d5b41b5d7f3596285dd672

28
src/where.c
View File

@ -2011,7 +2011,8 @@ static void whereUndoExprMods(WhereInfo *pWInfo){
/*
** Return TRUE if all of the following are true:
**
** (1) X has the same or lower cost that Y
** (1) X has the same or lower cost, or returns the same or fewer rows,
** than Y.
** (2) X uses fewer WHERE clause terms than Y
** (3) Every WHERE clause term used by X is also used by Y
** (4) X skips at least as many columns as Y
@ -2034,11 +2035,8 @@ static int whereLoopCheaperProperSubset(
if( pX->nLTerm-pX->nSkip >= pY->nLTerm-pY->nSkip ){
return 0; /* X is not a subset of Y */
}
if( pX->rRun>pY->rRun && pX->nOut>pY->nOut ) return 0;
if( pY->nSkip > pX->nSkip ) return 0;
if( pX->rRun >= pY->rRun ){
if( pX->rRun > pY->rRun ) return 0; /* X costs more than Y */
if( pX->nOut > pY->nOut ) return 0; /* X costs more than Y */
}
for(i=pX->nLTerm-1; i>=0; i--){
if( pX->aLTerm[i]==0 ) continue;
for(j=pY->nLTerm-1; j>=0; j--){
@ -2054,8 +2052,8 @@ static int whereLoopCheaperProperSubset(
}
/*
** Try to adjust the cost of WhereLoop pTemplate upwards or downwards so
** that:
** Try to adjust the cost and number of output rows of WhereLoop pTemplate
** upwards or downwards so that:
**
** (1) pTemplate costs less than any other WhereLoops that are a proper
** subset of pTemplate
@ -2076,16 +2074,20 @@ static void whereLoopAdjustCost(const WhereLoop *p, WhereLoop *pTemplate){
/* Adjust pTemplate cost downward so that it is cheaper than its
** subset p. */
WHERETRACE(0x80,("subset cost adjustment %d,%d to %d,%d\n",
pTemplate->rRun, pTemplate->nOut, p->rRun, p->nOut-1));
pTemplate->rRun = p->rRun;
pTemplate->nOut = p->nOut - 1;
pTemplate->rRun, pTemplate->nOut,
MIN(p->rRun, pTemplate->rRun),
MIN(p->nOut - 1, pTemplate->nOut)));
pTemplate->rRun = MIN(p->rRun, pTemplate->rRun);
pTemplate->nOut = MIN(p->nOut - 1, pTemplate->nOut);
}else if( whereLoopCheaperProperSubset(pTemplate, p) ){
/* Adjust pTemplate cost upward so that it is costlier than p since
** pTemplate is a proper subset of p */
WHERETRACE(0x80,("subset cost adjustment %d,%d to %d,%d\n",
pTemplate->rRun, pTemplate->nOut, p->rRun, p->nOut+1));
pTemplate->rRun = p->rRun;
pTemplate->nOut = p->nOut + 1;
pTemplate->rRun, pTemplate->nOut,
MAX(p->rRun, pTemplate->rRun),
MAX(p->nOut + 1, pTemplate->nOut)));
pTemplate->rRun = MAX(p->rRun, pTemplate->rRun);
pTemplate->nOut = MAX(p->nOut + 1, pTemplate->nOut);
}
}
}