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Merge the latest trunk changes (especially "PRAGMA busy_timeout" and the

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ORDER BY query planner optimizations) into the sessions branch.

FossilOrigin-Name: 6ca8eae1f89d19ee23cbc3a869d85b57d29b4a7d
This commit is contained in:
drh
2012-09-28 13:05:48 +00:00
parent 40eaa08620 f784c1ede9
commit c4645dacfb
80 changed files with 2418 additions and 1186 deletions
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140
src/insert.c
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@@ -320,6 +320,97 @@ void sqlite3AutoincrementEnd(Parse *pParse){
#endif /* SQLITE_OMIT_AUTOINCREMENT */
/*
** Generate code for a co-routine that will evaluate a subquery one
** row at a time.
**
** The pSelect parameter is the subquery that the co-routine will evaluation.
** Information about the location of co-routine and the registers it will use
** is returned by filling in the pDest object.
**
** Registers are allocated as follows:
**
** pDest->iSDParm The register holding the next entry-point of the
** co-routine. Run the co-routine to its next breakpoint
** by calling "OP_Yield $X" where $X is pDest->iSDParm.
**
** pDest->iSDParm+1 The register holding the "completed" flag for the
** co-routine. This register is 0 if the previous Yield
** generated a new result row, or 1 if the subquery
** has completed. If the Yield is called again
** after this register becomes 1, then the VDBE will
** halt with an SQLITE_INTERNAL error.
**
** pDest->iSdst First result register.
**
** pDest->nSdst Number of result registers.
**
** This routine handles all of the register allocation and fills in the
** pDest structure appropriately.
**
** Here is a schematic of the generated code assuming that X is the
** co-routine entry-point register reg[pDest->iSDParm], that EOF is the
** completed flag reg[pDest->iSDParm+1], and R and S are the range of
** registers that hold the result set, reg[pDest->iSdst] through
** reg[pDest->iSdst+pDest->nSdst-1]:
**
** X <- A
** EOF <- 0
** goto B
** A: setup for the SELECT
** loop rows in the SELECT
** load results into registers R..S
** yield X
** end loop
** cleanup after the SELECT
** EOF <- 1
** yield X
** halt-error
** B:
**
** To use this subroutine, the caller generates code as follows:
**
** [ Co-routine generated by this subroutine, shown above ]
** S: yield X
** if EOF goto E
** if skip this row, goto C
** if terminate loop, goto E
** deal with this row
** C: goto S
** E:
*/
int sqlite3CodeCoroutine(Parse *pParse, Select *pSelect, SelectDest *pDest){
int regYield; /* Register holding co-routine entry-point */
int regEof; /* Register holding co-routine completion flag */
int addrTop; /* Top of the co-routine */
int j1; /* Jump instruction */
int rc; /* Result code */
Vdbe *v; /* VDBE under construction */
regYield = ++pParse->nMem;
regEof = ++pParse->nMem;
v = sqlite3GetVdbe(pParse);
addrTop = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp2(v, OP_Integer, addrTop+2, regYield); /* X <- A */
VdbeComment((v, "Co-routine entry point"));
sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof); /* EOF <- 0 */
VdbeComment((v, "Co-routine completion flag"));
sqlite3SelectDestInit(pDest, SRT_Coroutine, regYield);
j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
rc = sqlite3Select(pParse, pSelect, pDest);
assert( pParse->nErr==0 || rc );
if( pParse->db->mallocFailed && rc==SQLITE_OK ) rc = SQLITE_NOMEM;
if( rc ) return rc;
sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof); /* EOF <- 1 */
sqlite3VdbeAddOp1(v, OP_Yield, regYield); /* yield X */
sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
VdbeComment((v, "End of coroutine"));
sqlite3VdbeJumpHere(v, j1); /* label B: */
return rc;
}
/* Forward declaration */
static int xferOptimization(
Parse *pParse, /* Parser context */
@@ -568,51 +659,12 @@ void sqlite3Insert(
** co-routine is the common header to the 3rd and 4th templates.
*/
if( pSelect ){
/* Data is coming from a SELECT. Generate code to implement that SELECT
** as a co-routine. The code is common to both the 3rd and 4th
** templates:
**
** EOF <- 0
** X <- A
** goto B
** A: setup for the SELECT
** loop over the tables in the SELECT
** load value into register R..R+n
** yield X
** end loop
** cleanup after the SELECT
** EOF <- 1
** yield X
** halt-error
**
** On each invocation of the co-routine, it puts a single row of the
** SELECT result into registers dest.iMem...dest.iMem+dest.nMem-1.
** (These output registers are allocated by sqlite3Select().) When
** the SELECT completes, it sets the EOF flag stored in regEof.
*/
int rc, j1;
regEof = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof); /* EOF <- 0 */
VdbeComment((v, "SELECT eof flag"));
sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
addrSelect = sqlite3VdbeCurrentAddr(v)+2;
sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iSDParm);
j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
VdbeComment((v, "Jump over SELECT coroutine"));
/* Resolve the expressions in the SELECT statement and execute it. */
rc = sqlite3Select(pParse, pSelect, &dest);
assert( pParse->nErr==0 || rc );
if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
goto insert_cleanup;
}
sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof); /* EOF <- 1 */
sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); /* yield X */
sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
VdbeComment((v, "End of SELECT coroutine"));
sqlite3VdbeJumpHere(v, j1); /* label B: */
/* Data is coming from a SELECT. Generate a co-routine to run that
** SELECT. */
int rc = sqlite3CodeCoroutine(pParse, pSelect, &dest);
if( rc ) goto insert_cleanup;
regEof = dest.iSDParm + 1;
regFromSelect = dest.iSdst;
assert( pSelect->pEList );
nColumn = pSelect->pEList->nExpr;