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

Improved comments an presentation for the recent IN operator decision

Browse Source 
improvement.

FossilOrigin-Name: 31e480f68dfd887cfd9114f9f9fec53d751d3ecc27e36f55c0166b51b2fbb08c
This commit is contained in:
drh 2018-06-09 14:13:46 +00:00
parent ccf6db5e64
commit a46ba6cca5
3 changed files with 10 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
manifest
View File

@ -1,5 +1,5 @@
C Performance\simprovement\sto\ssqlite3WhereExprUsage().
D 2018-06-09T02:49:11.362
C Improved\scomments\san\spresentation\sfor\sthe\srecent\sIN\soperator\sdecision\nimprovement.
D 2018-06-09T14:13:46.495
F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
F Makefile.in bfc40f350586923e0419d2ea4b559c37ec10ee4b6e210e08c14401f8e340f0da
@ -579,7 +579,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
F src/wal.c aa9cffc7a2bad6b826a86c8562dd4978398720ed41cb8ee7aa9d054eb8b456a0
F src/wal.h 8de5d2d3de0956d6f6cb48c83a4012d5f227b8fe940f3a349a4b7e85ebcb492a
F src/walker.c da987a20d40145c0a03c07d8fefcb2ed363becc7680d0500d9c79915591f5b1f
F src/where.c 9915929594a8c6bf8ca8d6e02a4f7e632948fa523712ab647490d18855a43656
F src/where.c fe1a6f97c12cc9472ccce86166ba3f827cf61d6ae770c036a6396b63863baac4
F src/whereInt.h b90ef9b9707ef750eab2a7a080c48fb4900315033274689def32d0cf5a81ebe4
F src/wherecode.c 3317f2b083a66d3e65a03edf316ade4ccb0a99c9956273282ebb579b95d4ba96
F src/whereexpr.c 6f022d6cc9daf56495f191b199352f783aff5cf268ba136b4d8cea3fb62d8c7d
@ -1731,7 +1731,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
P d735872ec383bbd220b08c61d25db9ff3675d2542b9e7867e7d6323a12e0cc23
R 2ba2d88f21c46106179a39d7ea349a11
P fd0934139076848f2f2edfd3d74d54608531031a05a60ca6ac1d7016dcd538df
R b9ed4417ad4e47d1ad0ea2ffe1b71005
U drh
Z 5dc11e9a5cd95e10cd947ae661eb7994
Z fc8a0aeffe4e41486a64c0cdfcf48c75

2
manifest.uuid
View File

@ -1 +1 @@
fd0934139076848f2f2edfd3d74d54608531031a05a60ca6ac1d7016dcd538df
31e480f68dfd887cfd9114f9f9fec53d751d3ecc27e36f55c0166b51b2fbb08c

5
src/where.c
View File

@ -2451,7 +2451,6 @@ static int whereLoopAddBtreeIndex(
if( eOp & WO_IN ){
Expr *pExpr = pTerm->pExpr;
LogEst M, logK;
if( ExprHasProperty(pExpr, EP_xIsSelect) ){
/* "x IN (SELECT ...)": TUNING: the SELECT returns 25 rows */
int i;
@ -2472,6 +2471,7 @@ static int whereLoopAddBtreeIndex(
** changes "x IN (?)" into "x=?". */
}
if( pProbe->hasStat1 ){
LogEst M, logK, safetyMargin;
/* Let:
** N = the total number of rows in the table
** K = the number of entries on the RHS of the IN operator
@ -2493,7 +2493,8 @@ static int whereLoopAddBtreeIndex(
*/
M = pProbe->aiRowLogEst[saved_nEq];
logK = estLog(nIn);
if( M + logK + 10 < nIn + rLogSize ){
safetyMargin = 10; /* TUNING: extra weight for indexed IN */
if( M + logK + safetyMargin < nIn + rLogSize ){
WHERETRACE(0x40,
("Scan preferred over IN operator on column %d of \"%s\" (%d<%d)\n",
saved_nEq, pProbe->zName, M+logK+10, nIn+rLogSize));