mirror of
https://github.com/alliedmodders/amxmodx.git
synced 2024-12-26 06:45:37 +03:00
b706108ed6
commit 011d9b6b07d904ad1e81ef7c747269903e2d47c4 Author: David Anderson <dvander@alliedmods.net> Date: Mon Jan 11 00:17:08 2010 -0600 Initial import from Subversion (amxmodx/trunk rev 3757).
404 lines
13 KiB
C
404 lines
13 KiB
C
/*
|
|
** 2005 July 8
|
|
**
|
|
** 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.
|
|
**
|
|
*************************************************************************
|
|
** This file contains code associated with the ANALYZE command.
|
|
**
|
|
** @(#) $Id: analyze.c 2779 2006-06-04 04:29:46Z damagedsoul $
|
|
*/
|
|
#ifndef SQLITE_OMIT_ANALYZE
|
|
#include "sqliteInt.h"
|
|
|
|
/*
|
|
** This routine generates code that opens the sqlite_stat1 table on cursor
|
|
** iStatCur.
|
|
**
|
|
** If the sqlite_stat1 tables does not previously exist, it is created.
|
|
** If it does previously exist, all entires associated with table zWhere
|
|
** are removed. If zWhere==0 then all entries are removed.
|
|
*/
|
|
static void openStatTable(
|
|
Parse *pParse, /* Parsing context */
|
|
int iDb, /* The database we are looking in */
|
|
int iStatCur, /* Open the sqlite_stat1 table on this cursor */
|
|
const char *zWhere /* Delete entries associated with this table */
|
|
){
|
|
sqlite3 *db = pParse->db;
|
|
Db *pDb;
|
|
int iRootPage;
|
|
Table *pStat;
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
|
|
pDb = &db->aDb[iDb];
|
|
if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
|
|
/* The sqlite_stat1 tables does not exist. Create it.
|
|
** Note that a side-effect of the CREATE TABLE statement is to leave
|
|
** the rootpage of the new table on the top of the stack. This is
|
|
** important because the OpenWrite opcode below will be needing it. */
|
|
sqlite3NestedParse(pParse,
|
|
"CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
|
|
pDb->zName
|
|
);
|
|
iRootPage = 0; /* Cause rootpage to be taken from top of stack */
|
|
}else if( zWhere ){
|
|
/* The sqlite_stat1 table exists. Delete all entries associated with
|
|
** the table zWhere. */
|
|
sqlite3NestedParse(pParse,
|
|
"DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
|
|
pDb->zName, zWhere
|
|
);
|
|
iRootPage = pStat->tnum;
|
|
}else{
|
|
/* The sqlite_stat1 table already exists. Delete all rows. */
|
|
iRootPage = pStat->tnum;
|
|
sqlite3VdbeAddOp(v, OP_Clear, pStat->tnum, iDb);
|
|
}
|
|
|
|
/* Open the sqlite_stat1 table for writing. Unless it was created
|
|
** by this vdbe program, lock it for writing at the shared-cache level.
|
|
** If this vdbe did create the sqlite_stat1 table, then it must have
|
|
** already obtained a schema-lock, making the write-lock redundant.
|
|
*/
|
|
if( iRootPage>0 ){
|
|
sqlite3TableLock(pParse, iDb, iRootPage, 1, "sqlite_stat1");
|
|
}
|
|
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
|
|
sqlite3VdbeAddOp(v, OP_OpenWrite, iStatCur, iRootPage);
|
|
sqlite3VdbeAddOp(v, OP_SetNumColumns, iStatCur, 3);
|
|
}
|
|
|
|
/*
|
|
** Generate code to do an analysis of all indices associated with
|
|
** a single table.
|
|
*/
|
|
static void analyzeOneTable(
|
|
Parse *pParse, /* Parser context */
|
|
Table *pTab, /* Table whose indices are to be analyzed */
|
|
int iStatCur, /* Cursor that writes to the sqlite_stat1 table */
|
|
int iMem /* Available memory locations begin here */
|
|
){
|
|
Index *pIdx; /* An index to being analyzed */
|
|
int iIdxCur; /* Cursor number for index being analyzed */
|
|
int nCol; /* Number of columns in the index */
|
|
Vdbe *v; /* The virtual machine being built up */
|
|
int i; /* Loop counter */
|
|
int topOfLoop; /* The top of the loop */
|
|
int endOfLoop; /* The end of the loop */
|
|
int addr; /* The address of an instruction */
|
|
int iDb; /* Index of database containing pTab */
|
|
|
|
v = sqlite3GetVdbe(pParse);
|
|
if( pTab==0 || pTab->pIndex==0 ){
|
|
/* Do no analysis for tables that have no indices */
|
|
return;
|
|
}
|
|
|
|
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
|
|
assert( iDb>=0 );
|
|
#ifndef SQLITE_OMIT_AUTHORIZATION
|
|
if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
|
|
pParse->db->aDb[iDb].zName ) ){
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
/* Establish a read-lock on the table at the shared-cache level. */
|
|
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
|
|
|
|
iIdxCur = pParse->nTab;
|
|
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
|
|
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
|
|
|
|
/* Open a cursor to the index to be analyzed
|
|
*/
|
|
assert( iDb==sqlite3SchemaToIndex(pParse->db, pIdx->pSchema) );
|
|
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
|
|
VdbeComment((v, "# %s", pIdx->zName));
|
|
sqlite3VdbeOp3(v, OP_OpenRead, iIdxCur, pIdx->tnum,
|
|
(char *)pKey, P3_KEYINFO_HANDOFF);
|
|
nCol = pIdx->nColumn;
|
|
if( iMem+nCol*2>=pParse->nMem ){
|
|
pParse->nMem = iMem+nCol*2+1;
|
|
}
|
|
sqlite3VdbeAddOp(v, OP_SetNumColumns, iIdxCur, nCol+1);
|
|
|
|
/* Memory cells are used as follows:
|
|
**
|
|
** mem[iMem]: The total number of rows in the table.
|
|
** mem[iMem+1]: Number of distinct values in column 1
|
|
** ...
|
|
** mem[iMem+nCol]: Number of distinct values in column N
|
|
** mem[iMem+nCol+1] Last observed value of column 1
|
|
** ...
|
|
** mem[iMem+nCol+nCol]: Last observed value of column N
|
|
**
|
|
** Cells iMem through iMem+nCol are initialized to 0. The others
|
|
** are initialized to NULL.
|
|
*/
|
|
for(i=0; i<=nCol; i++){
|
|
sqlite3VdbeAddOp(v, OP_MemInt, 0, iMem+i);
|
|
}
|
|
for(i=0; i<nCol; i++){
|
|
sqlite3VdbeAddOp(v, OP_MemNull, iMem+nCol+i+1, 0);
|
|
}
|
|
|
|
/* Do the analysis.
|
|
*/
|
|
endOfLoop = sqlite3VdbeMakeLabel(v);
|
|
sqlite3VdbeAddOp(v, OP_Rewind, iIdxCur, endOfLoop);
|
|
topOfLoop = sqlite3VdbeCurrentAddr(v);
|
|
sqlite3VdbeAddOp(v, OP_MemIncr, 1, iMem);
|
|
for(i=0; i<nCol; i++){
|
|
sqlite3VdbeAddOp(v, OP_Column, iIdxCur, i);
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, iMem+nCol+i+1, 0);
|
|
sqlite3VdbeAddOp(v, OP_Ne, 0x100, 0);
|
|
}
|
|
sqlite3VdbeAddOp(v, OP_Goto, 0, endOfLoop);
|
|
for(i=0; i<nCol; i++){
|
|
addr = sqlite3VdbeAddOp(v, OP_MemIncr, 1, iMem+i+1);
|
|
sqlite3VdbeChangeP2(v, topOfLoop + 3*i + 3, addr);
|
|
sqlite3VdbeAddOp(v, OP_Column, iIdxCur, i);
|
|
sqlite3VdbeAddOp(v, OP_MemStore, iMem+nCol+i+1, 1);
|
|
}
|
|
sqlite3VdbeResolveLabel(v, endOfLoop);
|
|
sqlite3VdbeAddOp(v, OP_Next, iIdxCur, topOfLoop);
|
|
sqlite3VdbeAddOp(v, OP_Close, iIdxCur, 0);
|
|
|
|
/* Store the results.
|
|
**
|
|
** The result is a single row of the sqlite_stmt1 table. The first
|
|
** two columns are the names of the table and index. The third column
|
|
** is a string composed of a list of integer statistics about the
|
|
** index. The first integer in the list is the total number of entires
|
|
** in the index. There is one additional integer in the list for each
|
|
** column of the table. This additional integer is a guess of how many
|
|
** rows of the table the index will select. If D is the count of distinct
|
|
** values and K is the total number of rows, then the integer is computed
|
|
** as:
|
|
**
|
|
** I = (K+D-1)/D
|
|
**
|
|
** If K==0 then no entry is made into the sqlite_stat1 table.
|
|
** If K>0 then it is always the case the D>0 so division by zero
|
|
** is never possible.
|
|
*/
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, iMem, 0);
|
|
addr = sqlite3VdbeAddOp(v, OP_IfNot, 0, 0);
|
|
sqlite3VdbeAddOp(v, OP_NewRowid, iStatCur, 0);
|
|
sqlite3VdbeOp3(v, OP_String8, 0, 0, pTab->zName, 0);
|
|
sqlite3VdbeOp3(v, OP_String8, 0, 0, pIdx->zName, 0);
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, iMem, 0);
|
|
sqlite3VdbeOp3(v, OP_String8, 0, 0, " ", 0);
|
|
for(i=0; i<nCol; i++){
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, iMem, 0);
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, iMem+i+1, 0);
|
|
sqlite3VdbeAddOp(v, OP_Add, 0, 0);
|
|
sqlite3VdbeAddOp(v, OP_AddImm, -1, 0);
|
|
sqlite3VdbeAddOp(v, OP_MemLoad, iMem+i+1, 0);
|
|
sqlite3VdbeAddOp(v, OP_Divide, 0, 0);
|
|
sqlite3VdbeAddOp(v, OP_ToInt, 0, 0);
|
|
if( i==nCol-1 ){
|
|
sqlite3VdbeAddOp(v, OP_Concat, nCol*2-1, 0);
|
|
}else{
|
|
sqlite3VdbeAddOp(v, OP_Dup, 1, 0);
|
|
}
|
|
}
|
|
sqlite3VdbeOp3(v, OP_MakeRecord, 3, 0, "aaa", 0);
|
|
sqlite3VdbeAddOp(v, OP_Insert, iStatCur, 0);
|
|
sqlite3VdbeJumpHere(v, addr);
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Generate code that will cause the most recent index analysis to
|
|
** be laoded into internal hash tables where is can be used.
|
|
*/
|
|
static void loadAnalysis(Parse *pParse, int iDb){
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
sqlite3VdbeAddOp(v, OP_LoadAnalysis, iDb, 0);
|
|
}
|
|
|
|
/*
|
|
** Generate code that will do an analysis of an entire database
|
|
*/
|
|
static void analyzeDatabase(Parse *pParse, int iDb){
|
|
sqlite3 *db = pParse->db;
|
|
Schema *pSchema = db->aDb[iDb].pSchema; /* Schema of database iDb */
|
|
HashElem *k;
|
|
int iStatCur;
|
|
int iMem;
|
|
|
|
sqlite3BeginWriteOperation(pParse, 0, iDb);
|
|
iStatCur = pParse->nTab++;
|
|
openStatTable(pParse, iDb, iStatCur, 0);
|
|
iMem = pParse->nMem;
|
|
for(k=sqliteHashFirst(&pSchema->tblHash); k; k=sqliteHashNext(k)){
|
|
Table *pTab = (Table*)sqliteHashData(k);
|
|
analyzeOneTable(pParse, pTab, iStatCur, iMem);
|
|
}
|
|
loadAnalysis(pParse, iDb);
|
|
}
|
|
|
|
/*
|
|
** Generate code that will do an analysis of a single table in
|
|
** a database.
|
|
*/
|
|
static void analyzeTable(Parse *pParse, Table *pTab){
|
|
int iDb;
|
|
int iStatCur;
|
|
|
|
assert( pTab!=0 );
|
|
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
|
|
sqlite3BeginWriteOperation(pParse, 0, iDb);
|
|
iStatCur = pParse->nTab++;
|
|
openStatTable(pParse, iDb, iStatCur, pTab->zName);
|
|
analyzeOneTable(pParse, pTab, iStatCur, pParse->nMem);
|
|
loadAnalysis(pParse, iDb);
|
|
}
|
|
|
|
/*
|
|
** Generate code for the ANALYZE command. The parser calls this routine
|
|
** when it recognizes an ANALYZE command.
|
|
**
|
|
** ANALYZE -- 1
|
|
** ANALYZE <database> -- 2
|
|
** ANALYZE ?<database>.?<tablename> -- 3
|
|
**
|
|
** Form 1 causes all indices in all attached databases to be analyzed.
|
|
** Form 2 analyzes all indices the single database named.
|
|
** Form 3 analyzes all indices associated with the named table.
|
|
*/
|
|
void sqlite3Analyze(Parse *pParse, Token *pName1, Token *pName2){
|
|
sqlite3 *db = pParse->db;
|
|
int iDb;
|
|
int i;
|
|
char *z, *zDb;
|
|
Table *pTab;
|
|
Token *pTableName;
|
|
|
|
/* Read the database schema. If an error occurs, leave an error message
|
|
** and code in pParse and return NULL. */
|
|
if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
|
|
return;
|
|
}
|
|
|
|
if( pName1==0 ){
|
|
/* Form 1: Analyze everything */
|
|
for(i=0; i<db->nDb; i++){
|
|
if( i==1 ) continue; /* Do not analyze the TEMP database */
|
|
analyzeDatabase(pParse, i);
|
|
}
|
|
}else if( pName2==0 || pName2->n==0 ){
|
|
/* Form 2: Analyze the database or table named */
|
|
iDb = sqlite3FindDb(db, pName1);
|
|
if( iDb>=0 ){
|
|
analyzeDatabase(pParse, iDb);
|
|
}else{
|
|
z = sqlite3NameFromToken(pName1);
|
|
pTab = sqlite3LocateTable(pParse, z, 0);
|
|
sqliteFree(z);
|
|
if( pTab ){
|
|
analyzeTable(pParse, pTab);
|
|
}
|
|
}
|
|
}else{
|
|
/* Form 3: Analyze the fully qualified table name */
|
|
iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pTableName);
|
|
if( iDb>=0 ){
|
|
zDb = db->aDb[iDb].zName;
|
|
z = sqlite3NameFromToken(pTableName);
|
|
pTab = sqlite3LocateTable(pParse, z, zDb);
|
|
sqliteFree(z);
|
|
if( pTab ){
|
|
analyzeTable(pParse, pTab);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
** Used to pass information from the analyzer reader through to the
|
|
** callback routine.
|
|
*/
|
|
typedef struct analysisInfo analysisInfo;
|
|
struct analysisInfo {
|
|
sqlite3 *db;
|
|
const char *zDatabase;
|
|
};
|
|
|
|
/*
|
|
** This callback is invoked once for each index when reading the
|
|
** sqlite_stat1 table.
|
|
**
|
|
** argv[0] = name of the index
|
|
** argv[1] = results of analysis - on integer for each column
|
|
*/
|
|
static int analysisLoader(void *pData, int argc, char **argv, char **azNotUsed){
|
|
analysisInfo *pInfo = (analysisInfo*)pData;
|
|
Index *pIndex;
|
|
int i, c;
|
|
unsigned int v;
|
|
const char *z;
|
|
|
|
assert( argc==2 );
|
|
if( argv==0 || argv[0]==0 || argv[1]==0 ){
|
|
return 0;
|
|
}
|
|
pIndex = sqlite3FindIndex(pInfo->db, argv[0], pInfo->zDatabase);
|
|
if( pIndex==0 ){
|
|
return 0;
|
|
}
|
|
z = argv[1];
|
|
for(i=0; *z && i<=pIndex->nColumn; i++){
|
|
v = 0;
|
|
while( (c=z[0])>='0' && c<='9' ){
|
|
v = v*10 + c - '0';
|
|
z++;
|
|
}
|
|
pIndex->aiRowEst[i] = v;
|
|
if( *z==' ' ) z++;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
** Load the content of the sqlite_stat1 table into the index hash tables.
|
|
*/
|
|
void sqlite3AnalysisLoad(sqlite3 *db, int iDb){
|
|
analysisInfo sInfo;
|
|
HashElem *i;
|
|
char *zSql;
|
|
|
|
/* Clear any prior statistics */
|
|
for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
|
|
Index *pIdx = sqliteHashData(i);
|
|
sqlite3DefaultRowEst(pIdx);
|
|
}
|
|
|
|
/* Check to make sure the sqlite_stat1 table existss */
|
|
sInfo.db = db;
|
|
sInfo.zDatabase = db->aDb[iDb].zName;
|
|
if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
|
|
return;
|
|
}
|
|
|
|
|
|
/* Load new statistics out of the sqlite_stat1 table */
|
|
zSql = sqlite3MPrintf("SELECT idx, stat FROM %Q.sqlite_stat1",
|
|
sInfo.zDatabase);
|
|
sqlite3SafetyOff(db);
|
|
sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
|
|
sqlite3SafetyOn(db);
|
|
sqliteFree(zSql);
|
|
}
|
|
|
|
|
|
#endif /* SQLITE_OMIT_ANALYZE */
|