database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-11-12 13:01:09 +03:00
Code Activity

Improved estimates of the relative speed of index scans based on declared

Browse Source 
datatypes of columns in the table.  Add "r" column to PRAGMA index_info,
showing the estimated relative scan rate.

FossilOrigin-Name: 07462bb6059f023c22a6c84a4a02afbd84e69255
This commit is contained in:
drh
2013-10-04 15:30:21 +00:00
parent d9e3cad2f8
commit fdaac671b8
7 changed files with 99 additions and 47 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
manifest
View File

@@ -1,5 +1,5 @@
C Progress\stoward\susing\sthe\siScanRatio\sinformation\son\sindices.\s\sMany\stests\nare\sstill\sfailing.
D 2013-10-04T02:36:19.375
C Improved\sestimates\sof\sthe\srelative\sspeed\sof\sindex\sscans\sbased\son\sdeclared\ndatatypes\sof\scolumns\sin\sthe\stable.\s\sAdd\s"r"\scolumn\sto\sPRAGMA\sindex_info,\nshowing\sthe\sestimated\srelative\sscan\srate.
D 2013-10-04T15:30:21.142
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -166,13 +166,13 @@ F src/btmutex.c 976f45a12e37293e32cae0281b15a21d48a8aaa7
F src/btree.c 5ccbbaed7a32ba774306f610da4ab4f3e5348294
F src/btree.h bfe0e8c5759b4ec77b0d18390064a6ef3cdffaaf
F src/btreeInt.h f038e818bfadf75afbd09819ed93c26a333d39e0
F src/build.c 7926e17a5dc3f698dd8b15511a4902f48c73ac50
F src/build.c 7a91b0db709404c8b606a6d8abcaf29b1bf75bbf
F src/callback.c f99a8957ba2adf369645fac0db09ad8adcf1caa2
F src/complete.c dc1d136c0feee03c2f7550bafc0d29075e36deac
F src/ctime.c ea4b7f3623a0fcb1146e7f245d7410033e86859c
F src/date.c 65196e95e69f36993659bd7781abe7c2f1994739
F src/delete.c 45788c5e48734f2af4acd75a876466e5b9838e34
F src/expr.c 1017f482217e093ecdaca91e8666681e83733252
F src/expr.c e7338ccffdc391c53ba2d51c5eb6a2f5299e040e
F src/fault.c 160a0c015b6c2629d3899ed2daf63d75754a32bb
F src/fkey.c be866cd8c4fa6cae98ba33109578fd1a3311ee5b
F src/func.c 2c47b65e6e00e3e9374942f28254faf8adafe398
@@ -210,7 +210,7 @@ F src/parse.y a97566d6da75075589a7c716d1bda14b586cf8da
F src/pcache.c f8043b433a57aba85384a531e3937a804432a346
F src/pcache.h a5e4f5d9f5d592051d91212c5949517971ae6222
F src/pcache1.c a467393909a4ed7ca9de066d85ba5c5b04a5be63
F src/pragma.c 5a4d8d9c3c7d22ef920487a260ea3d4b59d3b3a6
F src/pragma.c 3bcdc7a98ad9429218179d2d81fc4aa9e39d8592
F src/prepare.c fa6988589f39af8504a61731614cd4f6ae71554f
F src/printf.c da9119eb31a187a4b99f60aa4a225141c0ebb74b
F src/random.c 0b2dbc37fdfbfa6bd455b091dfcef5bdb32dba68
@@ -221,7 +221,7 @@ F src/shell.c 5ee50ca3e35453bbd6ccdf1bdd0f6bbe9738e9fb
F src/sqlite.h.in ec40aa958a270416fb04b4f72210357bf163d2c5
F src/sqlite3.rc 11094cc6a157a028b301a9f06b3d03089ea37c3e
F src/sqlite3ext.h 886f5a34de171002ad46fae8c36a7d8051c190fc
F src/sqliteInt.h c32d524facfb39084cc1a830aef0c31aeb93c04e
F src/sqliteInt.h da0e92df9550e57107aa43eab63b29d040fe9c80
F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
F src/status.c 7ac05a5c7017d0b9f0b4bcd701228b784f987158
F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -722,7 +722,7 @@ F test/pcache.test b09104b03160aca0d968d99e8cd2c5b1921a993d
F test/pcache2.test a83efe2dec0d392f814bfc998def1d1833942025
F test/percentile.test b98fc868d71eb5619d42a1702e9ab91718cbed54
F test/permutations.test 72f4f8881d388163ddbbeec0a6ed812e863ea2e6
F test/pragma.test 5e7de6c32a5d764f09437d2025f07e4917b9e178
F test/pragma.test de128f0253ee42a1edf6c80f21813babfb19bd3b
F test/pragma2.test 224f0381f9411a78ae685cac24c13656a62021b7
F test/printf.test ec9870c4dce8686a37818e0bf1aba6e6a1863552
F test/progress.test a282973d1d17f08071bc58a77d6b80f2a81c354d
@@ -1119,7 +1119,7 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
F tool/win/sqlite.vsix 030f3eeaf2cb811a3692ab9c14d021a75ce41fff
P d59d97b0a8d70dc31d45db61bbc11ebb5375a224
R 753a9b9a56a7c0c63483772726286f21
P 6c352edbba85a15ca356b5e131f4b3b2723d1774
R bacabbd9616babddd027da683b20e83a
U drh
Z b513b854bdc830eeffd07ca885795f7d
Z 469f9776554648d8f1435b44fd89545f

2
manifest.uuid
View File

@@ -1 +1 @@
6c352edbba85a15ca356b5e131f4b3b2723d1774
07462bb6059f023c22a6c84a4a02afbd84e69255

97
src/build.c
View File

@@ -1026,6 +1026,7 @@ void sqlite3AddColumn(Parse *pParse, Token *pName){
** be called next to set pCol->affinity correctly.
*/
pCol->affinity = SQLITE_AFF_NONE;
pCol->szEst = 1;
p->nCol++;
}
@@ -1067,15 +1068,18 @@ void sqlite3AddNotNull(Parse *pParse, int onError){
** If none of the substrings in the above table are found,
** SQLITE_AFF_NUMERIC is returned.
*/
char sqlite3AffinityType(const char *zIn){
char sqlite3AffinityType(const char *zIn, u8 *pszEst){
u32 h = 0;
char aff = SQLITE_AFF_NUMERIC;
const char *zChar;
if( zIn ) while( zIn[0] ){
if( zIn==0 ) return aff;
while( zIn[0] ){
h = (h<<8) + sqlite3UpperToLower[(*zIn)&0xff];
zIn++;
if( h==(('c'<<24)+('h'<<16)+('a'<<8)+'r') ){ /* CHAR */
aff = SQLITE_AFF_TEXT;
zChar = zIn;
}else if( h==(('c'<<24)+('l'<<16)+('o'<<8)+'b') ){ /* CLOB */
aff = SQLITE_AFF_TEXT;
}else if( h==(('t'<<24)+('e'<<16)+('x'<<8)+'t') ){ /* TEXT */
@@ -1099,7 +1103,25 @@ char sqlite3AffinityType(const char *zIn){
break;
}
}
if( pszEst ){
if( aff>=SQLITE_AFF_NUMERIC ){
*pszEst = 1;
}else if( zChar ){
*pszEst = 1;
while( zChar[0] ){
int v;
if( sqlite3Isdigit(zChar[0]) && sqlite3GetInt32(zChar, &v) ){
v = v/4 + 1;
if( v>255 ) v = 255;
*pszEst = v;
break;
}
zChar++;
}
}else{
*pszEst = 3;
}
}
return aff;
}
@@ -1121,7 +1143,7 @@ void sqlite3AddColumnType(Parse *pParse, Token *pType){
pCol = &p->aCol[p->nCol-1];
assert( pCol->zType==0 );
pCol->zType = sqlite3NameFromToken(pParse->db, pType);
pCol->affinity = sqlite3AffinityType(pCol->zType);
pCol->affinity = sqlite3AffinityType(pCol->zType, &pCol->szEst);
}
/*
@@ -1469,7 +1491,7 @@ static char *createTableStmt(sqlite3 *db, Table *p){
zType = azType[pCol->affinity - SQLITE_AFF_TEXT];
len = sqlite3Strlen30(zType);
assert( pCol->affinity==SQLITE_AFF_NONE
|| pCol->affinity==sqlite3AffinityType(zType) );
|| pCol->affinity==sqlite3AffinityType(zType, 0) );
memcpy(&zStmt[k], zType, len);
k += len;
assert( k<=n );
@@ -1478,6 +1500,39 @@ static char *createTableStmt(sqlite3 *db, Table *p){
return zStmt;
}
/*
** Estimate the total row width for a table.
*/
static unsigned estimatedTableWidth(const Table *pTab){
unsigned wTable = 0;
const Column *pTabCol;
int i;
for(i=pTab->nCol, pTabCol=pTab->aCol; i>0; i--, pTabCol++){
wTable += pTabCol->szEst;
}
if( pTab->iPKey<0 ) wTable++;
return wTable;
}
/*
** Set the iScanRatio for an index based on estimates of the average
** table row width and average index row width. Estimates are derived
** from the declared datatypes of the various columns.
*/
static void setIndexScanRatio(Index *pIdx, unsigned wTable){
unsigned wIndex = 1;
int i;
const Column *aCol = pIdx->pTable->aCol;
for(i=0; i<pIdx->nColumn; i++){
assert( pIdx->aiColumn[i]>=0 && pIdx->aiColumn[i]<pIdx->pTable->nCol );
wIndex += aCol[pIdx->aiColumn[i]].szEst;
}
assert( 100*wIndex/wTable <= 255 );
pIdx->iScanRatio = (u8)(128*wIndex/wTable);
/* printf("%s: wIndex=%d wTable=%d ratio=%d\n",
** pIdx->zName, wIndex, wTable, (100*pIdx->iScanRatio)/128); */
}
/*
** This routine is called to report the final ")" that terminates
** a CREATE TABLE statement.
@@ -1504,9 +1559,11 @@ void sqlite3EndTable(
Token *pEnd, /* The final ')' token in the CREATE TABLE */
Select *pSelect /* Select from a "CREATE ... AS SELECT" */
){
Table *p;
sqlite3 *db = pParse->db;
int iDb;
Table *p; /* The new table */
sqlite3 *db = pParse->db; /* The database connection */
int iDb; /* Database in which the table lives */
Index *pIdx; /* An implied index of the table */
unsigned wTable; /* Estimated average width of a row in the table */
if( (pEnd==0 && pSelect==0) || db->mallocFailed ){
return;
@@ -1526,6 +1583,12 @@ void sqlite3EndTable(
}
#endif /* !defined(SQLITE_OMIT_CHECK) */
/* Compute the iScanRatio of implied indices */
wTable = estimatedTableWidth(p);
for(pIdx=p->pIndex; pIdx; pIdx=pIdx->pNext){
setIndexScanRatio(pIdx, wTable);
}
/* If the db->init.busy is 1 it means we are reading the SQL off the
** "sqlite_master" or "sqlite_temp_master" table on the disk.
** So do not write to the disk again. Extract the root page number
@@ -2442,15 +2505,6 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
sqlite3VdbeAddOp1(v, OP_Close, iSorter);
}
/*
** Estimate the average width of a table column based on its affinity type.
*/
static unsigned estimatedColumnWidth(const Column *p){
if( p->affinity>=SQLITE_AFF_NUMERIC ) return 1;
if( p->affinity==SQLITE_AFF_TEXT ) return 3;
return 2;
}
/*
** Create a new index for an SQL table. pName1.pName2 is the name of the index
** and pTblList is the name of the table that is to be indexed. Both will
@@ -2493,8 +2547,6 @@ Index *sqlite3CreateIndex(
int iDb; /* Index of the database that is being written */
Token *pName = 0; /* Unqualified name of the index to create */
struct ExprList_item *pListItem; /* For looping over pList */
unsigned wTable = 0; /* Approximate "width" of the table */
unsigned wIndex = 0; /* Approximate "width" of this index */
const Column *pTabCol; /* A column in the table */
int nCol; /* Number of columns */
int nExtra = 0; /* Space allocated for zExtra[] */
@@ -2738,7 +2790,6 @@ Index *sqlite3CreateIndex(
goto exit_create_index;
}
pIndex->aiColumn[i] = j;
wIndex += estimatedColumnWidth(pTabCol);
if( pListItem->pExpr ){
int nColl;
assert( pListItem->pExpr->op==TK_COLLATE );
@@ -2762,11 +2813,9 @@ Index *sqlite3CreateIndex(
if( pTab->aCol[j].notNull==0 ) pIndex->uniqNotNull = 0;
}
sqlite3DefaultRowEst(pIndex);
for(j=pTab->nCol, pTabCol=pTab->aCol; j>0; j--, pTabCol++){
wTable += estimatedColumnWidth(pTabCol);
if( pParse->pNewTable==0 ){
setIndexScanRatio(pIndex, estimatedTableWidth(pTab));
}
assert( 100*wIndex/wTable <= 255 );
pIndex->iScanRatio = (u8)(128*wIndex/wTable);
if( pTab==pParse->pNewTable ){
/* This routine has been called to create an automatic index as a

6
src/expr.c
View File

@@ -41,7 +41,7 @@ char sqlite3ExprAffinity(Expr *pExpr){
#ifndef SQLITE_OMIT_CAST
if( op==TK_CAST ){
assert( !ExprHasProperty(pExpr, EP_IntValue) );
return sqlite3AffinityType(pExpr->u.zToken);
return sqlite3AffinityType(pExpr->u.zToken, 0);
}
#endif
if( (op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER)
@@ -2461,7 +2461,7 @@ int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){
int aff, to_op;
inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
assert( !ExprHasProperty(pExpr, EP_IntValue) );
aff = sqlite3AffinityType(pExpr->u.zToken);
aff = sqlite3AffinityType(pExpr->u.zToken, 0);
to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
assert( to_op==OP_ToText || aff!=SQLITE_AFF_TEXT );
assert( to_op==OP_ToBlob || aff!=SQLITE_AFF_NONE );
@@ -3128,7 +3128,7 @@ void sqlite3ExplainExpr(Vdbe *pOut, Expr *pExpr){
case TK_CAST: {
/* Expressions of the form: CAST(pLeft AS token) */
const char *zAff = "unk";
switch( sqlite3AffinityType(pExpr->u.zToken) ){
switch( sqlite3AffinityType(pExpr->u.zToken, 0) ){
case SQLITE_AFF_TEXT: zAff = "TEXT"; break;
case SQLITE_AFF_NONE: zAff = "NONE"; break;
case SQLITE_AFF_NUMERIC: zAff = "NUMERIC"; break;

8
src/pragma.c
View File

@@ -1455,17 +1455,19 @@ void sqlite3Pragma(
pIdx = pTab->pIndex;
if( pIdx ){
int i = 0;
sqlite3VdbeSetNumCols(v, 3);
pParse->nMem = 3;
sqlite3VdbeSetNumCols(v, 4);
pParse->nMem = 4;
sqlite3CodeVerifySchema(pParse, iDb);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", SQLITE_STATIC);
sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "r", SQLITE_STATIC);
while(pIdx){
sqlite3VdbeAddOp2(v, OP_Integer, i, 1);
sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, pIdx->zName, 0);
sqlite3VdbeAddOp2(v, OP_Integer, pIdx->onError!=OE_None, 3);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 3);
sqlite3VdbeAddOp2(v, OP_Integer, pIdx->iScanRatio*100/128, 4);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 4);
++i;
pIdx = pIdx->pNext;
}

5
src/sqliteInt.h
View File

@@ -1197,7 +1197,8 @@ struct Column {
char *zColl; /* Collating sequence. If NULL, use the default */
u8 notNull; /* An OE_ code for handling a NOT NULL constraint */
char affinity; /* One of the SQLITE_AFF_... values */
u16 colFlags; /* Boolean properties. See COLFLAG_ defines below */
u8 szEst; /* Estimated size of this column. INT==1 */
u8 colFlags; /* Boolean properties. See COLFLAG_ defines below */
};
/* Allowed values for Column.colFlags:
@@ -3082,7 +3083,7 @@ void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
void sqlite3AlterFinishAddColumn(Parse *, Token *);
void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
char sqlite3AffinityType(const char*);
char sqlite3AffinityType(const char*, u8*);
void sqlite3Analyze(Parse*, Token*, Token*);
int sqlite3InvokeBusyHandler(BusyHandler*);
int sqlite3FindDb(sqlite3*, Token*);

6
test/pragma.test
View File

@@ -574,7 +574,7 @@ ifcapable {foreignkey} {
execsql {
pragma index_list(t3);
}
} {0 sqlite_autoindex_t3_1 1}
} {/0 sqlite_autoindex_t3_1 1 \d+/}
}
ifcapable {!foreignkey} {
execsql {CREATE TABLE t3(a,b UNIQUE)}
@@ -647,7 +647,7 @@ do_test pragma-7.1.1 {
execsql {
pragma index_list(t3);
}
} {0 t3i1 0 1 sqlite_autoindex_t3_1 1}
} {/0 t3i1 0 \d+ 1 sqlite_autoindex_t3_1 1 \d+/}
do_test pragma-7.1.2 {
execsql {
pragma index_list(t3_bogus);
@@ -1661,7 +1661,7 @@ do_test 23.3 {
CREATE INDEX i3 ON t1(d,b,c);
}
db2 eval {PRAGMA index_list(t1)}
} {0 i3 0 1 i2 0 2 i1 0}
} {/0 i3 0 \d+ 1 i2 0 \d+ 2 i1 0 \d+/}
do_test 23.4 {
db eval {
ALTER TABLE t1 ADD COLUMN e;