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-rw-r--r--ext/misc/series.c120
1 files changed, 88 insertions, 32 deletions
diff --git a/ext/misc/series.c b/ext/misc/series.c
index abd6af7..0dfed18 100644
--- a/ext/misc/series.c
+++ b/ext/misc/series.c
@@ -103,16 +103,20 @@ SQLITE_EXTENSION_INIT1
** index is ix. The 0th member is given by smBase. The sequence members
** progress per ix increment by smStep.
*/
-static sqlite3_int64 genSeqMember(sqlite3_int64 smBase,
- sqlite3_int64 smStep,
- sqlite3_uint64 ix){
- if( ix>=(sqlite3_uint64)LLONG_MAX ){
+static sqlite3_int64 genSeqMember(
+ sqlite3_int64 smBase,
+ sqlite3_int64 smStep,
+ sqlite3_uint64 ix
+){
+ static const sqlite3_uint64 mxI64 =
+ ((sqlite3_uint64)0x7fffffff)<<32 | 0xffffffff;
+ if( ix>=mxI64 ){
/* Get ix into signed i64 range. */
- ix -= (sqlite3_uint64)LLONG_MAX;
+ ix -= mxI64;
/* With 2's complement ALU, this next can be 1 step, but is split into
* 2 for UBSAN's satisfaction (and hypothetical 1's complement ALUs.) */
- smBase += (LLONG_MAX/2) * smStep;
- smBase += (LLONG_MAX - LLONG_MAX/2) * smStep;
+ smBase += (mxI64/2) * smStep;
+ smBase += (mxI64 - mxI64/2) * smStep;
}
/* Under UBSAN (or on 1's complement machines), must do this last term
* in steps to avoid the dreaded (and harmless) signed multiply overlow. */
@@ -372,13 +376,13 @@ static int seriesEof(sqlite3_vtab_cursor *cur){
** parameter. (idxStr is not used in this implementation.) idxNum
** is a bitmask showing which constraints are available:
**
-** 1: start=VALUE
-** 2: stop=VALUE
-** 4: step=VALUE
-**
-** Also, if bit 8 is set, that means that the series should be output
-** in descending order rather than in ascending order. If bit 16 is
-** set, then output must appear in ascending order.
+** 0x01: start=VALUE
+** 0x02: stop=VALUE
+** 0x04: step=VALUE
+** 0x08: descending order
+** 0x10: ascending order
+** 0x20: LIMIT VALUE
+** 0x40: OFFSET VALUE
**
** This routine should initialize the cursor and position it so that it
** is pointing at the first row, or pointing off the end of the table
@@ -392,26 +396,44 @@ static int seriesFilter(
series_cursor *pCur = (series_cursor *)pVtabCursor;
int i = 0;
(void)idxStrUnused;
- if( idxNum & 1 ){
+ if( idxNum & 0x01 ){
pCur->ss.iBase = sqlite3_value_int64(argv[i++]);
}else{
pCur->ss.iBase = 0;
}
- if( idxNum & 2 ){
+ if( idxNum & 0x02 ){
pCur->ss.iTerm = sqlite3_value_int64(argv[i++]);
}else{
pCur->ss.iTerm = 0xffffffff;
}
- if( idxNum & 4 ){
+ if( idxNum & 0x04 ){
pCur->ss.iStep = sqlite3_value_int64(argv[i++]);
if( pCur->ss.iStep==0 ){
pCur->ss.iStep = 1;
}else if( pCur->ss.iStep<0 ){
- if( (idxNum & 16)==0 ) idxNum |= 8;
+ if( (idxNum & 0x10)==0 ) idxNum |= 0x08;
}
}else{
pCur->ss.iStep = 1;
}
+ if( idxNum & 0x20 ){
+ sqlite3_int64 iLimit = sqlite3_value_int64(argv[i++]);
+ sqlite3_int64 iTerm;
+ if( idxNum & 0x40 ){
+ sqlite3_int64 iOffset = sqlite3_value_int64(argv[i++]);
+ if( iOffset>0 ){
+ pCur->ss.iBase += pCur->ss.iStep*iOffset;
+ }
+ }
+ if( iLimit>=0 ){
+ iTerm = pCur->ss.iBase + (iLimit - 1)*pCur->ss.iStep;
+ if( pCur->ss.iStep<0 ){
+ if( iTerm>pCur->ss.iTerm ) pCur->ss.iTerm = iTerm;
+ }else{
+ if( iTerm<pCur->ss.iTerm ) pCur->ss.iTerm = iTerm;
+ }
+ }
+ }
for(i=0; i<argc; i++){
if( sqlite3_value_type(argv[i])==SQLITE_NULL ){
/* If any of the constraints have a NULL value, then return no rows.
@@ -422,7 +444,7 @@ static int seriesFilter(
break;
}
}
- if( idxNum & 8 ){
+ if( idxNum & 0x08 ){
pCur->ss.isReversing = pCur->ss.iStep > 0;
}else{
pCur->ss.isReversing = pCur->ss.iStep < 0;
@@ -442,10 +464,13 @@ static int seriesFilter(
**
** The query plan is represented by bits in idxNum:
**
-** (1) start = $value -- constraint exists
-** (2) stop = $value -- constraint exists
-** (4) step = $value -- constraint exists
-** (8) output in descending order
+** 0x01 start = $value -- constraint exists
+** 0x02 stop = $value -- constraint exists
+** 0x04 step = $value -- constraint exists
+** 0x08 output is in descending order
+** 0x10 output is in ascending order
+** 0x20 LIMIT $value -- constraint exists
+** 0x40 OFFSET $value -- constraint exists
*/
static int seriesBestIndex(
sqlite3_vtab *pVTab,
@@ -453,10 +478,12 @@ static int seriesBestIndex(
){
int i, j; /* Loop over constraints */
int idxNum = 0; /* The query plan bitmask */
+#ifndef ZERO_ARGUMENT_GENERATE_SERIES
int bStartSeen = 0; /* EQ constraint seen on the START column */
+#endif
int unusableMask = 0; /* Mask of unusable constraints */
int nArg = 0; /* Number of arguments that seriesFilter() expects */
- int aIdx[3]; /* Constraints on start, stop, and step */
+ int aIdx[5]; /* Constraints on start, stop, step, LIMIT, OFFSET */
const struct sqlite3_index_constraint *pConstraint;
/* This implementation assumes that the start, stop, and step columns
@@ -464,28 +491,54 @@ static int seriesBestIndex(
assert( SERIES_COLUMN_STOP == SERIES_COLUMN_START+1 );
assert( SERIES_COLUMN_STEP == SERIES_COLUMN_START+2 );
- aIdx[0] = aIdx[1] = aIdx[2] = -1;
+ aIdx[0] = aIdx[1] = aIdx[2] = aIdx[3] = aIdx[4] = -1;
pConstraint = pIdxInfo->aConstraint;
for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
int iCol; /* 0 for start, 1 for stop, 2 for step */
int iMask; /* bitmask for those column */
+ int op = pConstraint->op;
+ if( op>=SQLITE_INDEX_CONSTRAINT_LIMIT
+ && op<=SQLITE_INDEX_CONSTRAINT_OFFSET
+ ){
+ if( pConstraint->usable==0 ){
+ /* do nothing */
+ }else if( op==SQLITE_INDEX_CONSTRAINT_LIMIT ){
+ aIdx[3] = i;
+ idxNum |= 0x20;
+ }else{
+ assert( op==SQLITE_INDEX_CONSTRAINT_OFFSET );
+ aIdx[4] = i;
+ idxNum |= 0x40;
+ }
+ continue;
+ }
if( pConstraint->iColumn<SERIES_COLUMN_START ) continue;
iCol = pConstraint->iColumn - SERIES_COLUMN_START;
assert( iCol>=0 && iCol<=2 );
iMask = 1 << iCol;
- if( iCol==0 ) bStartSeen = 1;
+#ifndef ZERO_ARGUMENT_GENERATE_SERIES
+ if( iCol==0 && op==SQLITE_INDEX_CONSTRAINT_EQ ){
+ bStartSeen = 1;
+ }
+#endif
if( pConstraint->usable==0 ){
unusableMask |= iMask;
continue;
- }else if( pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
+ }else if( op==SQLITE_INDEX_CONSTRAINT_EQ ){
idxNum |= iMask;
aIdx[iCol] = i;
}
}
- for(i=0; i<3; i++){
+ if( aIdx[3]==0 ){
+ /* Ignore OFFSET if LIMIT is omitted */
+ idxNum &= ~0x60;
+ aIdx[4] = 0;
+ }
+ for(i=0; i<5; i++){
if( (j = aIdx[i])>=0 ){
pIdxInfo->aConstraintUsage[j].argvIndex = ++nArg;
- pIdxInfo->aConstraintUsage[j].omit = !SQLITE_SERIES_CONSTRAINT_VERIFY;
+ pIdxInfo->aConstraintUsage[j].omit =
+ !SQLITE_SERIES_CONSTRAINT_VERIFY || i>=3;
}
}
/* The current generate_column() implementation requires at least one
@@ -506,19 +559,22 @@ static int seriesBestIndex(
** this plan is unusable */
return SQLITE_CONSTRAINT;
}
- if( (idxNum & 3)==3 ){
+ if( (idxNum & 0x03)==0x03 ){
/* Both start= and stop= boundaries are available. This is the
** the preferred case */
pIdxInfo->estimatedCost = (double)(2 - ((idxNum&4)!=0));
pIdxInfo->estimatedRows = 1000;
if( pIdxInfo->nOrderBy>=1 && pIdxInfo->aOrderBy[0].iColumn==0 ){
if( pIdxInfo->aOrderBy[0].desc ){
- idxNum |= 8;
+ idxNum |= 0x08;
}else{
- idxNum |= 16;
+ idxNum |= 0x10;
}
pIdxInfo->orderByConsumed = 1;
}
+ }else if( (idxNum & 0x21)==0x21 ){
+ /* We have start= and LIMIT */
+ pIdxInfo->estimatedRows = 2500;
}else{
/* If either boundary is missing, we have to generate a huge span
** of numbers. Make this case very expensive so that the query
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-29 02:38:41 +0000