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1. Implemented binary search in array

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Oleg Bartunov
This commit is contained in:
Bruce Momjian 2001-10-04 15:41:14 +00:00
parent 720ca220a9
commit 7ff432c9ad
2 changed files with 20 additions and 24 deletions
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2
contrib/intarray/README.intarray
View File

@ -12,6 +12,8 @@ for additional information.
CHANGES:
October 1, 2001
1. Change search method in array to binary
September 28, 2001
1. gist__int_ops now is without lossy
2. add sort entry in picksplit

42
contrib/intarray/_int.c
View File

@ -1741,33 +1741,29 @@ makepol(WORKSTATE *state) {
typedef struct {
int4 *arrb;
int4 *arre;
int4 *ptr;
} CHKVAL;
/*
* is there value 'val' in array or not ?
*/
*/
static bool
checkcondition_arr( void *checkval, int4 val ) {
#ifdef BS_DEBUG
elog(NOTICE,"OPERAND %d", val);
#endif
if ( val > *(((CHKVAL*)checkval)->ptr) ) {
while ( ((CHKVAL*)checkval)->ptr < ((CHKVAL*)checkval)->arre ) {
((CHKVAL*)checkval)->ptr++;
if ( *(((CHKVAL*)checkval)->ptr) == val ) return true;
if ( val < *(((CHKVAL*)checkval)->ptr) ) return false;
}
} else if ( val < *(((CHKVAL*)checkval)->ptr) ) {
while ( ((CHKVAL*)checkval)->ptr > ((CHKVAL*)checkval)->arrb ) {
((CHKVAL*)checkval)->ptr--;
if ( *(((CHKVAL*)checkval)->ptr) == val ) return true;
if ( val > *(((CHKVAL*)checkval)->ptr) ) return false;
}
} else {
return true;
int4 *StopLow = ((CHKVAL*)checkval)->arrb;
int4 *StopHigh = ((CHKVAL*)checkval)->arre;
int4 *StopMiddle;
/* Loop invariant: StopLow <= val < StopHigh */
while (StopLow < StopHigh) {
StopMiddle = StopLow + (StopHigh - StopLow) / 2;
if (*StopMiddle == val)
return (true);
else if (*StopMiddle < val )
StopLow = StopMiddle + 1;
else
StopHigh = StopMiddle;
}
return false;
return false;
}
static bool
@ -1818,8 +1814,7 @@ execconsistent( QUERYTYPE *query, ArrayType *array, bool calcnot ) {
CHKVAL chkval;
chkval.arrb = ARRPTR(array);
chkval.arre = chkval.arrb + ARRNELEMS(array) - 1;
chkval.ptr = chkval.arrb + ARRNELEMS(array)/2;
chkval.arre = chkval.arrb + ARRNELEMS(array);
return execute(
GETQUERY(query) + query->size-1 ,
(void*)&chkval, calcnot,
@ -1854,8 +1849,7 @@ boolop(PG_FUNCTION_ARGS) {
PREPAREARR(val);
chkval.arrb = ARRPTR(val);
chkval.arre = chkval.arrb + ARRNELEMS(val) - 1;
chkval.ptr = chkval.arrb + ARRNELEMS(val)/2;
chkval.arre = chkval.arrb + ARRNELEMS(val);
result = execute(
GETQUERY(query) + query->size-1 ,
&chkval, true,