database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-08-07 02:42:48 +03:00
Code Activity

Optimize simple min() and max() queries. (CVS 382)

Browse Source 
FossilOrigin-Name: cc5abfe392bdb8c3ed00e0610bc2b41851bfc9d7
This commit is contained in:
drh
2002-02-19 15:00:07 +00:00
parent aaab5725db
commit 9562b55115
7 changed files with 287 additions and 130 deletions
Download Patch File Download Diff File Expand all files Collapse all files

78
src/vdbe.c
View File

@@ -30,7 +30,7 @@
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** $Id: vdbe.c,v 1.118 2002/02/19 13:39:23 drh Exp $
** $Id: vdbe.c,v 1.119 2002/02/19 15:00:08 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -866,29 +866,30 @@ static char *zOpName[] = { 0,
"Close", "MoveTo", "NewRecno", "PutIntKey",
"PutStrKey", "Distinct", "Found", "NotFound",
"IsUnique", "NotExists", "Delete", "Column",
"KeyAsData", "Recno", "FullKey", "Rewind",
"Next", "Destroy", "Clear", "CreateIndex",
"CreateTable", "IntegrityCk", "IdxPut", "IdxDelete",
"IdxRecno", "IdxGT", "IdxGE", "MemLoad",
"MemStore", "ListWrite", "ListRewind", "ListRead",
"ListReset", "SortPut", "SortMakeRec", "SortMakeKey",
"Sort", "SortNext", "SortCallback", "SortReset",
"FileOpen", "FileRead", "FileColumn", "AggReset",
"AggFocus", "AggIncr", "AggNext", "AggSet",
"AggGet", "SetInsert", "SetFound", "SetNotFound",
"MakeRecord", "MakeKey", "MakeIdxKey", "IncrKey",
"Goto", "If", "Halt", "ColumnCount",
"ColumnName", "Callback", "NullCallback", "Integer",
"String", "Pop", "Dup", "Pull",
"Push", "MustBeInt", "Add", "AddImm",
"Subtract", "Multiply", "Divide", "Remainder",
"BitAnd", "BitOr", "BitNot", "ShiftLeft",
"ShiftRight", "AbsValue", "Precision", "Min",
"Max", "Like", "Glob", "Eq",
"Ne", "Lt", "Le", "Gt",
"Ge", "IsNull", "NotNull", "Negative",
"And", "Or", "Not", "Concat",
"Noop", "Strlen", "Substr", "Limit",
"KeyAsData", "Recno", "FullKey", "Last",
"Rewind", "Next", "Destroy", "Clear",
"CreateIndex", "CreateTable", "IntegrityCk", "IdxPut",
"IdxDelete", "IdxRecno", "IdxGT", "IdxGE",
"MemLoad", "MemStore", "ListWrite", "ListRewind",
"ListRead", "ListReset", "SortPut", "SortMakeRec",
"SortMakeKey", "Sort", "SortNext", "SortCallback",
"SortReset", "FileOpen", "FileRead", "FileColumn",
"AggReset", "AggFocus", "AggIncr", "AggNext",
"AggSet", "AggGet", "SetInsert", "SetFound",
"SetNotFound", "MakeRecord", "MakeKey", "MakeIdxKey",
"IncrKey", "Goto", "If", "Halt",
"ColumnCount", "ColumnName", "Callback", "NullCallback",
"Integer", "String", "Pop", "Dup",
"Pull", "Push", "MustBeInt", "Add",
"AddImm", "Subtract", "Multiply", "Divide",
"Remainder", "BitAnd", "BitOr", "BitNot",
"ShiftLeft", "ShiftRight", "AbsValue", "Precision",
"Min", "Max", "Like", "Glob",
"Eq", "Ne", "Lt", "Le",
"Gt", "Ge", "IsNull", "NotNull",
"Negative", "And", "Or", "Not",
"Concat", "Noop", "Strlen", "Substr",
"Limit",
};
/*
@@ -3096,7 +3097,11 @@ case OP_Column: {
/* Figure out how many bytes in the column data and where the column
** data begins.
*/
if( payloadSize<256 ){
if( payloadSize==0 ){
aStack[tos].flags = STK_Null;
p->tos = tos;
break;
}else if( payloadSize<256 ){
idxWidth = 1;
}else if( payloadSize<65536 ){
idxWidth = 2;
@@ -3216,6 +3221,29 @@ case OP_FullKey: {
break;
}
/* Opcode: Last P1 P2 *
**
** The next use of the Recno or Column or Next instruction for P1
** will refer to the last entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
*/
case OP_Last: {
int i = pOp->p1;
BtCursor *pCrsr;
if( VERIFY( i>=0 && i<p->nCursor && ) (pCrsr = p->aCsr[i].pCursor)!=0 ){
int res;
sqliteBtreeLast(pCrsr, &res);
p->aCsr[i].atFirst = res==0;
if( res && pOp->p2>0 ){
pc = pOp->p2 - 1;
}
}
break;
}
/* Opcode: Rewind P1 P2 *
**
** The next use of the Recno or Column or Next instruction for P1