postgresql/src/backend/utils/adt/not_in.c

/*-------------------------------------------------------------------------
 *
 * not_in.c--
 *    Executes the "not_in" operator for any data type
 *
 * Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *    $Header: /cvsroot/pgsql/src/backend/utils/adt/Attic/not_in.c,v 1.3 1997/08/19 21:34:48 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
/*
 *
 * XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 * X HACK WARNING!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! X
 * XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 *
 * This code is the OLD not-in code that is HACKED
 * into place until operators that can have arguments as
 * columns are ******REALLY****** implemented!!!!!!!!!!!
 *
 */
#include <stdio.h>
#include <string.h>
#include "postgres.h"
#include "access/heapam.h"
#include "access/relscan.h"
#include "utils/builtins.h"	/* where function decls go */

static int my_varattno(Relation rd, char *a);

/* ----------------------------------------------------------------
 *	
 * ----------------------------------------------------------------
 */
bool
int4notin(int16 not_in_arg, char *relation_and_attr)
{
    Relation relation_to_scan;
    int left_side_argument, integer_value;
    HeapTuple current_tuple;
    HeapScanDesc scan_descriptor;
    bool dummy, retval;
    int attrid;
    char *relation, *attribute;
    char my_copy[32];
    Datum value;
    NameData relNameData;
    ScanKeyData skeyData;
    
    strcpy(my_copy, relation_and_attr);
    
    relation = (char *) strtok(my_copy, ".");
    attribute = (char *) strtok(NULL, ".");
    
    
    /* fetch tuple OID */
    
    left_side_argument = not_in_arg;
    
    /* Open the relation and get a relation descriptor */
    
    namestrcpy(&relNameData,relation);
    relation_to_scan = heap_openr(relNameData.data);
    attrid  = my_varattno(relation_to_scan, attribute);

    /* the last argument should be a ScanKey, not an integer! - jolly*/
    /* it looks like the arguments are out of order, too */
    /* but skeyData is never initialized! does this work?? - ay 2/95 */
    scan_descriptor = heap_beginscan(relation_to_scan, false, NULL, 0,
				     &skeyData); 

    retval = true;
    
    /* do a scan of the relation, and do the check */
    for (current_tuple = heap_getnext(scan_descriptor, 0, NULL);
         current_tuple != NULL && retval;
         current_tuple = heap_getnext(scan_descriptor, 0, NULL))
	{
	    value = PointerGetDatum(heap_getattr(current_tuple,
						 InvalidBuffer,
						 (AttrNumber) attrid,
				 RelationGetTupleDescriptor(relation_to_scan),
						 &dummy));
	    
	    integer_value = DatumGetInt16(value);
	    if (left_side_argument == integer_value)
		{
		    retval = false;
		}
	}
    
    /* close the relation */
    heap_close(relation_to_scan);
    return(retval);
}

bool oidnotin(Oid the_oid, char *compare)
{
    if (the_oid == InvalidOid)
	return false;
    return(int4notin(the_oid, compare));
}

/*
 * XXX
 * If varattno (in parser/catalog_utils.h) ever is added to
 * cinterface.a, this routine should go away
 */
static int my_varattno(Relation rd, char *a)
{
    int i;
    
    for (i = 0; i < rd->rd_rel->relnatts; i++) {
	if (!namestrcmp(&rd->rd_att->attrs[i]->attname, a)) {
	    return(i+1);
	}
    }
    return(-1);
}