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705 lines (640 loc) · 22.3 KB
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/*
** 2010 July 12
**
** 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 an implementation of the "dbstat" virtual table.
**
** The dbstat virtual table is used to extract low-level formatting
** information from an SQLite database in order to implement the
** "sqlite3_analyzer" utility. See the ../tool/spaceanal.tcl script
** for an example implementation.
**
** Additional information is available on the "dbstat.html" page of the
** official SQLite documentation.
*/
#include "sqliteInt.h" /* Requires access to internal data structures */
#if (defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)) \
&& !defined(SQLITE_OMIT_VIRTUALTABLE)
/*
** Page paths:
**
** The value of the 'path' column describes the path taken from the
** root-node of the b-tree structure to each page. The value of the
** root-node path is '/'.
**
** The value of the path for the left-most child page of the root of
** a b-tree is '/000/'. (Btrees store content ordered from left to right
** so the pages to the left have smaller keys than the pages to the right.)
** The next to left-most child of the root page is
** '/001', and so on, each sibling page identified by a 3-digit hex
** value. The children of the 451st left-most sibling have paths such
** as '/1c2/000/, '/1c2/001/' etc.
**
** Overflow pages are specified by appending a '+' character and a
** six-digit hexadecimal value to the path to the cell they are linked
** from. For example, the three overflow pages in a chain linked from
** the left-most cell of the 450th child of the root page are identified
** by the paths:
**
** '/1c2/000+000000' // First page in overflow chain
** '/1c2/000+000001' // Second page in overflow chain
** '/1c2/000+000002' // Third page in overflow chain
**
** If the paths are sorted using the BINARY collation sequence, then
** the overflow pages associated with a cell will appear earlier in the
** sort-order than its child page:
**
** '/1c2/000/' // Left-most child of 451st child of root
*/
#define VTAB_SCHEMA \
"CREATE TABLE xx( " \
" name TEXT, /* Name of table or index */" \
" path TEXT, /* Path to page from root */" \
" pageno INTEGER, /* Page number */" \
" pagetype TEXT, /* 'internal', 'leaf' or 'overflow' */" \
" ncell INTEGER, /* Cells on page (0 for overflow) */" \
" payload INTEGER, /* Bytes of payload on this page */" \
" unused INTEGER, /* Bytes of unused space on this page */" \
" mx_payload INTEGER, /* Largest payload size of all cells */" \
" pgoffset INTEGER, /* Offset of page in file */" \
" pgsize INTEGER, /* Size of the page */" \
" schema TEXT HIDDEN /* Database schema being analyzed */" \
");"
typedef struct StatTable StatTable;
typedef struct StatCursor StatCursor;
typedef struct StatPage StatPage;
typedef struct StatCell StatCell;
struct StatCell {
int nLocal; /* Bytes of local payload */
u32 iChildPg; /* Child node (or 0 if this is a leaf) */
int nOvfl; /* Entries in aOvfl[] */
u32 *aOvfl; /* Array of overflow page numbers */
int nLastOvfl; /* Bytes of payload on final overflow page */
int iOvfl; /* Iterates through aOvfl[] */
};
struct StatPage {
u32 iPgno;
DbPage *pPg;
int iCell;
char *zPath; /* Path to this page */
/* Variables populated by statDecodePage(): */
u8 flags; /* Copy of flags byte */
int nCell; /* Number of cells on page */
int nUnused; /* Number of unused bytes on page */
StatCell *aCell; /* Array of parsed cells */
u32 iRightChildPg; /* Right-child page number (or 0) */
int nMxPayload; /* Largest payload of any cell on this page */
};
struct StatCursor {
sqlite3_vtab_cursor base;
sqlite3_stmt *pStmt; /* Iterates through set of root pages */
int isEof; /* After pStmt has returned SQLITE_DONE */
int iDb; /* Schema used for this query */
StatPage aPage[32];
int iPage; /* Current entry in aPage[] */
/* Values to return. */
char *zName; /* Value of 'name' column */
char *zPath; /* Value of 'path' column */
u32 iPageno; /* Value of 'pageno' column */
char *zPagetype; /* Value of 'pagetype' column */
int nCell; /* Value of 'ncell' column */
int nPayload; /* Value of 'payload' column */
int nUnused; /* Value of 'unused' column */
int nMxPayload; /* Value of 'mx_payload' column */
i64 iOffset; /* Value of 'pgOffset' column */
int szPage; /* Value of 'pgSize' column */
};
struct StatTable {
sqlite3_vtab base;
sqlite3 *db;
int iDb; /* Index of database to analyze */
};
#ifndef get2byte
# define get2byte(x) ((x)[0]<<8 | (x)[1])
#endif
/*
** Connect to or create a statvfs virtual table.
*/
static int statConnect(
sqlite3 *db,
void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVtab,
char **pzErr
){
StatTable *pTab = 0;
int rc = SQLITE_OK;
int iDb;
if( argc>=4 ){
Token nm;
sqlite3TokenInit(&nm, (char*)argv[3]);
iDb = sqlite3FindDb(db, &nm);
if( iDb<0 ){
*pzErr = sqlite3_mprintf("no such database: %s", argv[3]);
return SQLITE_ERROR;
}
}else{
iDb = 0;
}
rc = sqlite3_declare_vtab(db, VTAB_SCHEMA);
if( rc==SQLITE_OK ){
pTab = (StatTable *)sqlite3_malloc64(sizeof(StatTable));
if( pTab==0 ) rc = SQLITE_NOMEM_BKPT;
}
assert( rc==SQLITE_OK || pTab==0 );
if( rc==SQLITE_OK ){
memset(pTab, 0, sizeof(StatTable));
<
10BC0
div>
pTab->db = db;
pTab->iDb = iDb;
}
*ppVtab = (sqlite3_vtab*)pTab;
return rc;
}
/*
** Disconnect from or destroy a statvfs virtual table.
*/
static int statDisconnect(sqlite3_vtab *pVtab){
sqlite3_free(pVtab);
return SQLITE_OK;
}
/*
** There is no "best-index". This virtual table always does a linear
** scan. However, a schema=? constraint should cause this table to
** operate on a different database schema, so check for it.
**
** idxNum is normally 0, but will be 1 if a schema=? constraint exists.
*/
static int statBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
int i;
pIdxInfo->estimatedCost = 1.0e6; /* Initial cost estimate */
/* Look for a valid schema=? constraint. If found, change the idxNum to
** 1 and request the value of that constraint be sent to xFilter. And
** lower the cost estimate to encourage the constrained version to be
** used.
*/
for(i=0; i<pIdxInfo->nConstraint; i++){
if( pIdxInfo->aConstraint[i].usable==0 ) continue;
if( pIdxInfo->aConstraint[i].op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
if( pIdxInfo->aConstraint[i].iColumn!=10 ) continue;
pIdxInfo->idxNum = 1;
pIdxInfo->estimatedCost = 1.0;
pIdxInfo->aConstraintUsage[i].argvIndex = 1;
pIdxInfo->aConstraintUsage[i].omit = 1;
break;
}
/* Records are always returned in ascending order of (name, path).
** If this will satisfy the client, set the orderByConsumed flag so that
** SQLite does not do an external sort.
*/
if( ( pIdxInfo->nOrderBy==1
&& pIdxInfo->aOrderBy[0].iColumn==0
&& pIdxInfo->aOrderBy[0].desc==0
) ||
( pIdxInfo->nOrderBy==2
&& pIdxInfo->aOrderBy[0].iColumn==0
&& pIdxInfo->aOrderBy[0].desc==0
&& pIdxInfo->aOrderBy[1].iColumn==1
&& pIdxInfo->aOrderBy[1].desc==0
)
){
pIdxInfo->orderByConsumed = 1;
}
return SQLITE_OK;
}
/*
** Open a new statvfs cursor.
*/
static int statOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
StatTable *pTab = (StatTable *)pVTab;
StatCursor *pCsr;
pCsr = (StatCursor *)sqlite3_malloc64(sizeof(StatCursor));
if( pCsr==0 ){
return SQLITE_NOMEM_BKPT;
}else{
memset(pCsr, 0, sizeof(StatCursor));
pCsr->base.pVtab = pVTab;
pCsr->iDb = pTab->iDb;
}
*ppCursor = (sqlite3_vtab_cursor *)pCsr;
return SQLITE_OK;
}
static void statClearPage(StatPage *p){
int i;
if( p->aCell ){
for(i=0; i<p->nCell; i++){
sqlite3_free(p->aCell[i].aOvfl);
}
sqlite3_free(p->aCell);
}
sqlite3PagerUnref(p->pPg);
sqlite3_free(p->zPath);
memset(p, 0, sizeof(StatPage));
}
static void statResetCsr(StatCursor *pCsr){
int i;
sqlite3_reset(pCsr->pStmt);
for(i=0; i<ArraySize(pCsr->aPage); i++){
statClearPage(&pCsr->aPage[i]);
}
pCsr->iPage = 0;
sqlite3_free(pCsr->zPath);
pCsr->zPath = 0;
pCsr->isEof = 0;
}
/*
** Close a statvfs cursor.
*/
static int statClose(sqlite3_vtab_cursor *pCursor){
StatCursor *pCsr = (StatCursor *)pCursor;
statResetCsr(pCsr);
sqlite3_finalize(pCsr->pStmt);
sqlite3_free(pCsr);
return SQLITE_OK;
}
static void getLocalPayload(
int nUsable, /* Usable bytes per page */
u8 flags, /* Page flags */
int nTotal, /* Total record (payload) size */
int *pnLocal /* OUT: Bytes stored locally */
){
int nLocal;
int nMinLocal;
int nMaxLocal;
if( flags==0x0D ){ /* Table leaf node */
nMinLocal = (nUsable - 12) * 32 / 255 - 23;
nMaxLocal = nUsable - 35;
}else{ /* Index interior and leaf nodes */
nMinLocal = (nUsable - 12) * 32 / 255 - 23;
nMaxLocal = (nUsable - 12) * 64 / 255 - 23;
}
nLocal = nMinLocal + (nTotal - nMinLocal) % (nUsable - 4);
if( nLocal>nMaxLocal ) nLocal = nMinLocal;
*pnLocal = nLocal;
}
static int statDecodePage(Btree *pBt, StatPage *p){
int nUnused;
int iOff;
int nHdr;
int isLeaf;
int szPage;
u8 *aData = sqlite3PagerGetData(p->pPg);
u8 *aHdr = &aData[p->iPgno==1 ? 100 : 0];
p->flags = aHdr[0];
p->nCell = get2byte(&aHdr[3]);
p->nMxPayload = 0;
isLeaf = (p->flags==0x0A || p->flags==0x0D);
nHdr = 12 - isLeaf*4 + (p->iPgno==1)*100;
nUnused = get2byte(&aHdr[5]) - nHdr - 2*p->nCell;
nUnused += (int)aHdr[7];
iOff = get2byte(&aHdr[1]);
while( iOff ){
nUnused += get2byte(&aData[iOff+2]);
iOff = get2byte(&aData[iOff]);
}
p->nUnused = nUnused;
p->iRightChildPg = isLeaf ? 0 : sqlite3Get4byte(&aHdr[8]);
szPage = sqlite3BtreeGetPageSize(pBt);
if( p->nCell ){
int i; /* Used to iterate through cells */
int nUsable; /* Usable bytes per page */
sqlite3BtreeEnter(pBt);
nUsable = szPage - sqlite3BtreeGetReserveNoMutex(pBt);
sqlite3BtreeLeave(pBt);
p->aCell = sqlite3_malloc64((p->nCell+1) * sizeof(StatCell));
if( p->aCell==0 ) return SQLITE_NOMEM_BKPT;
memset(p->aCell, 0, (p->nCell+1) * sizeof(StatCell));
for(i=0; i<p->nCell; i++){
StatCell *pCell = &p->aCell[i];
iOff = get2byte(&aData[nHdr+i*2]);
if( !isLeaf ){
pCell->iChildPg = sqlite3Get4byte(&aData[iOff]);
iOff += 4;
}
if( p->flags==0x05 ){
/* A table interior node. nPayload==0. */
}else{
u32 nPayload; /* Bytes of payload total (local+overflow) */
int nLocal; /* Bytes of payload stored locally */
iOff += getVarint32(&aData[iOff], nPayload);
if( p->flags==0x0D ){
u64 dummy;
iOff += sqlite3GetVarint(&aData[iOff], &dummy);
}
if( nPayload>(u32)p->nMxPayload ) p->nMxPayload = nPayload;
getLocalPayload(nUsable, p->flags, nPayload, &nLocal);
pCell->nLocal = nLocal;
assert( nLocal>=0 );
assert( nPayload>=(u32)nLocal );
assert( nLocal<=(nUsable-35) );
if( nPayload>(u32)nLocal ){
int j;
int nOvfl = ((nPayload - nLocal) + nUsable-4 - 1) / (nUsable - 4);
pCell->nLastOvfl = (nPayload-nLocal) - (nOvfl-1) * (nUsable-4);
pCell->nOvfl = nOvfl;
pCell->aOvfl = sqlite3_malloc64(sizeof(u32)*nOvfl);
if( pCell->aOvfl==0 ) return SQLITE_NOMEM_BKPT;
pCell->aOvfl[0] = sqlite3Get4byte(&aData[iOff+nLocal]);
for(j=1; j<nOvfl; j++){
int rc;
u32 iPrev = pCell->aOvfl[j-1];
DbPage *pPg = 0;
rc = sqlite3PagerGet(sqlite3BtreePager(pBt), iPrev, &pPg, 0);
if( rc!=SQLITE_OK ){
assert( pPg==0 );
return rc;
}
pCell->aOvfl[j] = sqlite3Get4byte(sqlite3PagerGetData(pPg));
sqlite3PagerUnref(pPg);
}
}
}
}
}
return SQLITE_OK;
}
/*
** Populate the pCsr->iOffset and pCsr->szPage member variables. Based on
** the current value of pCsr->iPageno.
*/
static void statSizeAndOffset(StatCursor *pCsr){
StatTable *pTab = (StatTable *)((sqlite3_vtab_cursor *)pCsr)->pVtab;
Btree *pBt = pTab->db->aDb[pTab->iDb].pBt;
Pager *pPager = sqlite3BtreePager(pBt);
sqlite3_file *fd;
sqlite3_int64 x[2];
/* The default page size and offset */
pCsr->szPage = sqlite3BtreeGetPageSize(pBt);
pCsr->iOffset = (i64)pCsr->szPage * (pCsr->iPageno - 1);
/* If connected to a ZIPVFS backend, override the page size and
** offset with actual values obtained from ZIPVFS.
*/
fd = sqlite3PagerFile(pPager);
x[0] = pCsr->iPageno;
if( fd->pMethods!=0 && sqlite3OsFileControl(fd, 230440, &x)==SQLITE_OK ){
pCsr->iOffset = x[0];
pCsr->szPage = (int)x[1];
}
}
/*
** Move a statvfs cursor to the next entry in the file.
*/
static int statNext(sqlite3_vtab_cursor *pCursor){
int rc;
int nPayload;
char *z;
StatCursor *pCsr = (StatCursor *)pCursor;
StatTable *pTab = (StatTable *)pCursor->pVtab;
Btree *pBt = pTab->db->aDb[pCsr->iDb].pBt;
Pager *pPager = sqlite3BtreePager(pBt);
sqlite3_free(pCsr->zPath);
pCsr->zPath = 0;
statNextRestart:
if( pCsr->aPage[0].pPg==0 ){
rc = sqlite3_step(pCsr->pStmt);
if( rc==SQLITE_ROW ){
int nPage;
u32 iRoot = (u32)sqlite3_column_int64(pCsr->pStmt, 1);
sqlite3PagerPagecount(pPager, &nPage);
if( nPage==0 ){
pCsr->isEof = 1;
return sqlite3_reset(pCsr->pStmt);
}
rc = sqlite3PagerGet(pPager, iRoot, &pCsr->aPage[0].pPg, 0);
pCsr->aPage[0].iPgno = iRoot;
pCsr->aPage[0].iCell = 0;
pCsr->aPage[0].zPath = z = sqlite3_mprintf("/");
pCsr->iPage = 0;
if( z==0 ) rc = SQLITE_NOMEM_BKPT;
}else{
pCsr->isEof = 1;
return sqlite3_reset(pCsr->pStmt);
}
}else{
/* Page p itself has already been visited. */
StatPage *p = &pCsr->aPage[pCsr->iPage];
while( p->iCell<p->nCell ){
StatCell *pCell = &p->aCell[p->iCell];
if( pCell->iOvfl<pCell->nOvfl ){
int nUsable;
sqlite3BtreeEnter(pBt);
nUsable = sqlite3BtreeGetPageSize(pBt) -
sqlite3BtreeGetReserveNoMutex(pBt);
sqlite3BtreeLeave(pBt);
pCsr->zName = (char *)sqlite3_column_text(pCsr->pStmt, 0);
pCsr->iPageno = pCell->aOvfl[pCell->iOvfl];
pCsr->zPagetype = "overflow";
pCsr->nCell = 0;
pCsr->nMxPayload = 0;
pCsr->zPath = z = sqlite3_mprintf(
"%s%.3x+%.6x", p->zPath, p->iCell, pCell->iOvfl
);
if( pCell->iOvfl<pCell->nOvfl-1 ){
pCsr->nUnused = 0;
pCsr->nPayload = nUsable - 4;
}else{
pCsr->nPayload = pCell->nLastOvfl;
pCsr->nUnused = nUsable - 4 - pCsr->nPayload;
}
pCell->iOvfl++;
statSizeAndOffset(pCsr);
return z==0 ? SQLITE_NOMEM_BKPT : SQLITE_OK;
}
if( p->iRightChildPg ) break;
p->iCell++;
}
if( !p->iRightChildPg || p->iCell>p->nCell ){
statClearPage(p);
if( pCsr->iPage==0 ) return statNext(pCursor);
pCsr->iPage--;
goto statNextRestart; /* Tail recursion */
}
pCsr->iPage++;
assert( p==&pCsr->aPage[pCsr->iPage-1] );
if( p->iCell==p->nCell ){
p[1].iPgno = p->iRightChildPg;
}else{
p[1].iPgno = p->aCell[p->iCell].iChildPg;
}
rc = sqlite3PagerGet(pPager, p[1].iPgno, &p[1].pPg, 0);
p[1].iCell = 0;
p[1].zPath = z = sqlite3_mprintf("%s%.3x/", p->zPath, p->iCell);
p->iCell++;
if( z==0 ) rc = SQLITE_NOMEM_BKPT;
}
/* Populate the StatCursor fields with the values to be returned
** by the xColumn() and xRowid() methods.
*/
if( rc==SQLITE_OK ){
int i;
StatPage *p = &pCsr->aPage[pCsr->iPage];
pCsr->zName = (char *)sqlite3_column_text(pCsr->pStmt, 0);
pCsr->iPageno = p->iPgno;
rc = statDecodePage(pBt, p);
if( rc==SQLITE_OK ){
statSizeAndOffset(pCsr);
switch( p->flags ){
case 0x05: /* table internal */
case 0x02: /* index internal */
pCsr->zPagetype = "internal";
break;
case 0x0D: /* table leaf */
case 0x0A: /* index leaf */
pCsr->zPagetype = "leaf";
break;
default:
pCsr->zPagetype = "corrupted";
break;
}
pCsr->nCell = p->nCell;
pCsr->nUnused = p->nUnused;
pCsr->nMxPayload = p->nMxPayload;
pCsr->zPath = z = sqlite3_mprintf("%s", p->zPath);
if( z==0 ) rc = SQLITE_NOMEM_BKPT;
nPayload = 0;
for(i=0; i<p->nCell; i++){
nPayload += p->aCell[i].nLocal;
}
pCsr->nPayload = nPayload;
}
}
return rc;
}
static int statEof(sqlite3_vtab_cursor *pCursor){
StatCursor *pCsr = (StatCursor *)pCursor;
return pCsr->isEof;
}
static int statFilter(
sqlite3_vtab_cursor *pCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
StatCursor *pCsr = (StatCursor *)pCursor;
StatTable *pTab = (StatTable*)(pCursor->pVtab);
char *zSql;
int rc = SQLITE_OK;
char *zMaster;
if( idxNum==1 ){
const char *zDbase = (const char*)sqlite3_value_text(argv[0]);
pCsr->iDb = sqlite3FindDbName(pTab->db, zDbase);
if( pCsr->iDb<0 ){
sqlite3_free(pCursor->pVtab->zErrMsg);
pCursor->pVtab->zErrMsg = sqlite3_mprintf("no such schema: %s", zDbase);
return pCursor->pVtab->zErrMsg ? SQLITE_ERROR : SQLITE_NOMEM_BKPT;
}
}else{
pCsr->iDb = pTab->iDb;
}
statResetCsr(pCsr);
sqlite3_finalize(pCsr->pStmt);
pCsr->pStmt = 0;
zMaster = pCsr->iDb==1 ? "sqlite_temp_master" : "sqlite_master";
zSql = sqlite3_mprintf(
"SELECT 'sqlite_master' AS name, 1 AS rootpage, 'table' AS type"
" UNION ALL "
"SELECT name, rootpage, type"
" FROM \"%w\".%s WHERE rootpage!=0"
" ORDER BY name", pTab->db->aDb[pCsr->iDb].zDbSName, zMaster);
if( zSql==0 ){
return SQLITE_NOMEM_BKPT;
}else{
rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pStmt, 0);
sqlite3_free(zSql);
}
if( rc==SQLITE_OK ){
rc = statNext(pCursor);
}
return rc;
}
static int statColumn(
sqlite3_vtab_cursor *pCursor,
sqlite3_context *ctx,
int i
){
StatCursor *pCsr = (StatCursor *)pCursor;
switch( i ){
case 0: /* name */
sqlite3_result_text(ctx, pCsr->zName, -1, SQLITE_TRANSIENT);
break;
case 1: /* path */
sqlite3_result_text(ctx, pCsr->zPath, -1, SQLITE_TRANSIENT);
break;
case 2: /* pageno */
sqlite3_result_int64(ctx, pCsr->iPageno);
break;
case 3: /* pagetype */
sqlite3_result_text(ctx, pCsr->zPagetype, -1, SQLITE_STATIC);
break;
case 4: /* ncell */
sqlite3_result_int(ctx, pCsr->nCell);
break;
case 5: /* payload */
sqlite3_result_int(ctx, pCsr->nPayload);
break;
case 6: /* unused */
sqlite3_result_int(ctx, pCsr->nUnused);
break;
case 7: /* mx_payload */
sqlite3_result_int(ctx, pCsr->nMxPayload);
break;
case 8: /* pgoffset */
sqlite3_result_int64(ctx, pCsr->iOffset);
break;
case 9: /* pgsize */
sqlite3_result_int(ctx, pCsr->szPage);
break;
default: { /* schema */
sqlite3 *db = sqlite3_context_db_handle(ctx);
int iDb = pCsr->iDb;
sqlite3_result_text(ctx, db->aDb[iDb].zDbSName, -1, SQLITE_STATIC);
break;
}
}
return SQLITE_OK;
}
static int statRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
StatCursor *pCsr = (StatCursor *)pCursor;
*pRowid = pCsr->iPageno;
return SQLITE_OK;
}
/*
** Invoke this routine to register the "dbstat" virtual table module
*/
int sqlite3DbstatRegister(sqlite3 *db){
static sqlite3_module dbstat_module = {
0, /* iVersion */
statConnect, /* xCreate */
statConnect, /* xConnect */
statBestIndex, /* xBestIndex */
statDisconnect, /* xDisconnect */
statDisconnect, /* xDestroy */
statOpen, /* xOpen - open a cursor */
statClose, /* xClose - close a cursor */
statFilter, /* xFilter - configure scan constraints */
statNext, /* xNext - advance a cursor */
statEof, /* xEof - check for end of scan */
statColumn, /* xColumn - read data */
statRowid, /* xRowid - read data */
0, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
0, /* xSavepoint */
0, /* xRelease */
0, /* xRollbackTo */
};
return sqlite3_create_module(db, "dbstat", &dbstat_module, 0);
}
#elif defined(SQLITE_ENABLE_DBSTAT_VTAB)
int sqlite3DbstatRegister(sqlite3 *db){ return SQLITE_OK; }
#endif /* SQLITE_ENABLE_DBSTAT_VTAB */