@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $ PostgreSQL : pgsql / src / backend / utils / adt / arrayfuncs . c , v 1.130 2006 / 07 / 14 14 : 52 : 23 momjian Exp $
* $ PostgreSQL : pgsql / src / backend / utils / adt / arrayfuncs . c , v 1.131 2006 / 09 / 10 20 : 14 : 20 tgl Exp $
*
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
@ -3345,6 +3345,232 @@ array_cmp(FunctionCallInfo fcinfo)
}
/*-----------------------------------------------------------------------------
* array overlap / containment comparisons
* These use the same methods of comparing array elements as array_eq .
* We consider only the elements of the arrays , ignoring dimensionality .
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
*/
/*
* array_contain_compare :
* compares two arrays for overlap / containment
*
* When matchall is true , return true if all members of array1 are in array2 .
* When matchall is false , return true if any members of array1 are in array2 .
*/
static bool
array_contain_compare ( ArrayType * array1 , ArrayType * array2 , bool matchall ,
void * * fn_extra )
{
bool result = matchall ;
Oid element_type = ARR_ELEMTYPE ( array1 ) ;
TypeCacheEntry * typentry ;
int nelems1 ;
Datum * values2 ;
bool * nulls2 ;
int nelems2 ;
int typlen ;
bool typbyval ;
char typalign ;
char * ptr1 ;
bits8 * bitmap1 ;
int bitmask ;
int i ;
int j ;
FunctionCallInfoData locfcinfo ;
if ( element_type ! = ARR_ELEMTYPE ( array2 ) )
ereport ( ERROR ,
( errcode ( ERRCODE_DATATYPE_MISMATCH ) ,
errmsg ( " cannot compare arrays of different element types " ) ) ) ;
/*
* We arrange to look up the equality function only once per series of
* calls , assuming the element type doesn ' t change underneath us . The
* typcache is used so that we have no memory leakage when being used
* as an index support function .
*/
typentry = ( TypeCacheEntry * ) * fn_extra ;
if ( typentry = = NULL | |
typentry - > type_id ! = element_type )
{
typentry = lookup_type_cache ( element_type ,
TYPECACHE_EQ_OPR_FINFO ) ;
if ( ! OidIsValid ( typentry - > eq_opr_finfo . fn_oid ) )
ereport ( ERROR ,
( errcode ( ERRCODE_UNDEFINED_FUNCTION ) ,
errmsg ( " could not identify an equality operator for type %s " ,
format_type_be ( element_type ) ) ) ) ;
* fn_extra = ( void * ) typentry ;
}
typlen = typentry - > typlen ;
typbyval = typentry - > typbyval ;
typalign = typentry - > typalign ;
/*
* Since we probably will need to scan array2 multiple times , it ' s
* worthwhile to use deconstruct_array on it . We scan array1 the hard way
* however , since we very likely won ' t need to look at all of it .
*/
deconstruct_array ( array2 , element_type , typlen , typbyval , typalign ,
& values2 , & nulls2 , & nelems2 ) ;
/*
* Apply the comparison operator to each pair of array elements .
*/
InitFunctionCallInfoData ( locfcinfo , & typentry - > eq_opr_finfo , 2 ,
NULL , NULL ) ;
/* Loop over source data */
nelems1 = ArrayGetNItems ( ARR_NDIM ( array1 ) , ARR_DIMS ( array1 ) ) ;
ptr1 = ARR_DATA_PTR ( array1 ) ;
bitmap1 = ARR_NULLBITMAP ( array1 ) ;
bitmask = 1 ;
for ( i = 0 ; i < nelems1 ; i + + )
{
Datum elt1 ;
bool isnull1 ;
/* Get element, checking for NULL */
if ( bitmap1 & & ( * bitmap1 & bitmask ) = = 0 )
{
isnull1 = true ;
elt1 = ( Datum ) 0 ;
}
else
{
isnull1 = false ;
elt1 = fetch_att ( ptr1 , typbyval , typlen ) ;
ptr1 = att_addlength ( ptr1 , typlen , PointerGetDatum ( ptr1 ) ) ;
ptr1 = ( char * ) att_align ( ptr1 , typalign ) ;
}
/* advance bitmap pointer if any */
bitmask < < = 1 ;
if ( bitmask = = 0x100 )
{
if ( bitmap1 )
bitmap1 + + ;
bitmask = 1 ;
}
/*
* We assume that the comparison operator is strict , so a NULL
* can ' t match anything . XXX this diverges from the " NULL=NULL "
* behavior of array_eq , should we act like that ?
*/
if ( isnull1 )
{
if ( matchall )
{
result = false ;
break ;
}
continue ;
}
for ( j = 0 ; j < nelems2 ; j + + )
{
Datum elt2 = values2 [ j ] ;
bool isnull2 = nulls2 [ j ] ;
bool oprresult ;
if ( isnull2 )
continue ; /* can't match */
/*
* Apply the operator to the element pair
*/
locfcinfo . arg [ 0 ] = elt1 ;
locfcinfo . arg [ 1 ] = elt2 ;
locfcinfo . argnull [ 0 ] = false ;
locfcinfo . argnull [ 1 ] = false ;
locfcinfo . isnull = false ;
oprresult = DatumGetBool ( FunctionCallInvoke ( & locfcinfo ) ) ;
if ( oprresult )
break ;
}
if ( j < nelems2 )
{
/* found a match for elt1 */
if ( ! matchall )
{
result = true ;
break ;
}
}
else
{
/* no match for elt1 */
if ( matchall )
{
result = false ;
break ;
}
}
}
pfree ( values2 ) ;
pfree ( nulls2 ) ;
return result ;
}
Datum
arrayoverlap ( PG_FUNCTION_ARGS )
{
ArrayType * array1 = PG_GETARG_ARRAYTYPE_P ( 0 ) ;
ArrayType * array2 = PG_GETARG_ARRAYTYPE_P ( 1 ) ;
bool result ;
result = array_contain_compare ( array1 , array2 , false ,
& fcinfo - > flinfo - > fn_extra ) ;
/* Avoid leaking memory when handed toasted input. */
PG_FREE_IF_COPY ( array1 , 0 ) ;
PG_FREE_IF_COPY ( array2 , 1 ) ;
PG_RETURN_BOOL ( result ) ;
}
Datum
arraycontains ( PG_FUNCTION_ARGS )
{
ArrayType * array1 = PG_GETARG_ARRAYTYPE_P ( 0 ) ;
ArrayType * array2 = PG_GETARG_ARRAYTYPE_P ( 1 ) ;
bool result ;
result = array_contain_compare ( array2 , array1 , true ,
& fcinfo - > flinfo - > fn_extra ) ;
/* Avoid leaking memory when handed toasted input. */
PG_FREE_IF_COPY ( array1 , 0 ) ;
PG_FREE_IF_COPY ( array2 , 1 ) ;
PG_RETURN_BOOL ( result ) ;
}
Datum
arraycontained ( PG_FUNCTION_ARGS )
{
ArrayType * array1 = PG_GETARG_ARRAYTYPE_P ( 0 ) ;
ArrayType * array2 = PG_GETARG_ARRAYTYPE_P ( 1 ) ;
bool result ;
result = array_contain_compare ( array1 , array2 , true ,
& fcinfo - > flinfo - > fn_extra ) ;
/* Avoid leaking memory when handed toasted input. */
PG_FREE_IF_COPY ( array1 , 0 ) ;
PG_FREE_IF_COPY ( array2 , 1 ) ;
PG_RETURN_BOOL ( result ) ;
}
/***************************************************************************/
/******************| Support Routines |*****************/
/***************************************************************************/
Tom Lane
20 years ago