Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Change sqlite3_blob_reopen() to call sqlite3VdbeExec() directly rather than going through sqlite3_step(). Performance enhancement. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
347df3c1fd7322e7aacaf1e9f8be8183 |
| User & Date: | drh 2017-01-21 16:27:56 |
Context
|
2017-01-22
| ||
| 00:11 | Fix an initialized variable in kvtest. check-in: ed62c5a6 user: drh tags: trunk | |
|
2017-01-21
| ||
| 16:54 | B-tree optimization: When seeking on a rowid table that has already been positioned, check to see if the new row happens to be the next row on the same leaf page. That is a reasonably common case, and if it is true it avoids a full binary search. check-in: 8e5cfb20 user: drh tags: btree-moveto-neighbor | |
| 16:27 | Change sqlite3_blob_reopen() to call sqlite3VdbeExec() directly rather than going through sqlite3_step(). Performance enhancement. check-in: 347df3c1 user: drh tags: trunk | |
| 15:55 | In the kvtest.c test utility, reuse the buffer into which blobs are read, rather than reallocating it for each row. This is a closer match to how other test programs work, and thus provides a better comparison. check-in: 0d1ad13a user: drh tags: trunk | |
Changes
Changes to src/vdbeblob.c.
22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 .. 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 ... 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 |
** Valid sqlite3_blob* handles point to Incrblob structures.
*/
typedef struct Incrblob Incrblob;
struct Incrblob {
int nByte; /* Size of open blob, in bytes */
int iOffset; /* Byte offset of blob in cursor data */
u16 iCol; /* Table column this handle is open on */
u8 isPureKV; /* True if pTab is a pure key/value table */
BtCursor *pCsr; /* Cursor pointing at blob row */
sqlite3_stmt *pStmt; /* Statement holding cursor open */
sqlite3 *db; /* The associated database */
char *zDb; /* Database name */
Table *pTab; /* Table object */
};
................................................................................
** calls to sqlite3_blob_read(), blob_write() or blob_reopen() will
** immediately return SQLITE_ABORT.
*/
static int blobSeekToRow(Incrblob *p, sqlite3_int64 iRow, char **pzErr){
int rc; /* Error code */
char *zErr = 0; /* Error message */
Vdbe *v = (Vdbe *)p->pStmt;
/* Set the value of register r[1] in the SQL statement to integer iRow.
** This is done directly as a performance optimization
*/
v->aMem[1].flags = MEM_Int;
v->aMem[1].u.i = iRow;
/* If the statement has been run before (and is paused at the OP_ResultRow)
** then back it up to the point where it does the OP_SeekRowid. This could
** have been down with an extra OP_Goto, but simply setting the program
** counter is faster. */
if( v->pc>3 ) v->pc = 3;
rc = sqlite3_step(p->pStmt);
if( rc==SQLITE_ROW ){
VdbeCursor *pC = v->apCsr[0];
u32 type = pC->aType[p->iCol];
if( type<12 ){
zErr = sqlite3MPrintf(p->db, "cannot open value of type %s",
type==0?"null": type==7?"real": "integer"
);
................................................................................
pParse->nVar = 0;
pParse->nMem = 1;
pParse->nTab = 1;
sqlite3VdbeMakeReady(v, pParse);
}
}
pBlob->isPureKV = (pTab->nCol==2 && pTab->iPKey==0);
pBlob->iCol = iCol;
pBlob->db = db;
sqlite3BtreeLeaveAll(db);
if( db->mallocFailed ){
goto blob_open_out;
}
rc = blobSeekToRow(pBlob, iRow, &zErr);
|
< > | < > > > > > | > < |
22 23 24 25 26 27 28 29 30 31 32 33 34 35 .. 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 ... 319 320 321 322 323 324 325 326 327 328 329 330 331 332 |
** Valid sqlite3_blob* handles point to Incrblob structures.
*/
typedef struct Incrblob Incrblob;
struct Incrblob {
int nByte; /* Size of open blob, in bytes */
int iOffset; /* Byte offset of blob in cursor data */
u16 iCol; /* Table column this handle is open on */
BtCursor *pCsr; /* Cursor pointing at blob row */
sqlite3_stmt *pStmt; /* Statement holding cursor open */
sqlite3 *db; /* The associated database */
char *zDb; /* Database name */
Table *pTab; /* Table object */
};
................................................................................
** calls to sqlite3_blob_read(), blob_write() or blob_reopen() will
** immediately return SQLITE_ABORT.
*/
static int blobSeekToRow(Incrblob *p, sqlite3_int64 iRow, char **pzErr){
int rc; /* Error code */
char *zErr = 0; /* Error message */
Vdbe *v = (Vdbe *)p->pStmt;
sqlite3 *db = v->db;
/* Set the value of register r[1] in the SQL statement to integer iRow.
** This is done directly as a performance optimization
*/
v->aMem[1].flags = MEM_Int;
v->aMem[1].u.i = iRow;
/* If the statement has been run before (and is paused at the OP_ResultRow)
** then back it up to the point where it does the OP_SeekRowid. This could
** have been down with an extra OP_Goto, but simply setting the program
** counter is faster. */
if( v->pc>3 ){
v->pc = 3;
db->nVdbeExec++;
rc = sqlite3VdbeExec((Vdbe*)p->pStmt);
db->nVdbeExec--;
}else{
rc = sqlite3_step(p->pStmt);
}
if( rc==SQLITE_ROW ){
VdbeCursor *pC = v->apCsr[0];
u32 type = pC->aType[p->iCol];
if( type<12 ){
zErr = sqlite3MPrintf(p->db, "cannot open value of type %s",
type==0?"null": type==7?"real": "integer"
);
................................................................................
pParse->nVar = 0;
pParse->nMem = 1;
pParse->nTab = 1;
sqlite3VdbeMakeReady(v, pParse);
}
}
pBlob->iCol = iCol;
pBlob->db = db;
sqlite3BtreeLeaveAll(db);
if( db->mallocFailed ){
goto blob_open_out;
}
rc = blobSeekToRow(pBlob, iRow, &zErr);
|