/* ----------------------------------------------------------------
* caql_getattr()
* during beginscan/endscan iteration, get a tuple attribute for
* current tuple
* ----------------------------------------------------------------
*/
Datum
caql_getattr(cqContext *pCtx, AttrNumber attnum, bool *isnull)
{
Assert(HeapTupleIsValid(pCtx->cq_lasttup));
return caql_getattr_internal(pCtx, pCtx->cq_lasttup, attnum, isnull);
}
Datum caql_getattr(cqContext *pCtx, AttrNumber attnum, bool *isnull)
{
Assert(HeapTupleIsValid(pCtx->cq_lasttup));
return caql_getattr_internal(pCtx, pCtx->cq_lasttup, attnum, isnull);
/*
NOTE: could this be used if caql is extended to support joins, eg
what would attnum be for
"SELECT * FROM pg_resqueue, pg_resqueuecapability ..." ?
Potentially, the attnum is just the ordinal position of the combined
SELECT list, eg you could reference pg_resqueuecapability.restypid
as (Natts_pg_resqueue+Anum_pg_resourcetype_restypid).
*/
}
/* ----------------------------------------------------------------
* caql_getcstring_plus()
* Return a cstring column from the first tuple and end the scan.
* ----------------------------------------------------------------
*/
char *caql_getcstring_plus(cqContext *pCtx0, int *pFetchcount,
bool *pbIsNull, cq_list *pcql)
{
const char *caql_str = pcql->caqlStr;
const char *filenam = pcql->filename;
int lineno = pcql->lineno;
struct caql_hash_cookie *pchn = cq_lookup(caql_str, strlen(caql_str), pcql);
cqContext *pCtx;
cqContext cqc;
HeapTuple tuple;
char *result = NULL;
if (NULL == pchn)
elog(ERROR, "invalid caql string: %s\nfile: %s, line %d",
caql_str, filenam, lineno);
Assert(!pchn->bInsert); /* INSERT not allowed */
/* use the provided context, or provide a clean local ctx */
if (pCtx0)
pCtx = pCtx0;
else
pCtx = cqclr(&cqc);
pCtx = caql_switch(pchn, pCtx, pcql);
/* NOTE: caql_switch frees the pcql */
if (pFetchcount)
*pFetchcount = 0;
if (pbIsNull)
*pbIsNull = true;
/* use the SysCache */
if (pCtx->cq_usesyscache)
{
tuple = SearchSysCacheKeyArray(pCtx->cq_cacheId,
pCtx->cq_NumKeys,
pCtx->cq_cacheKeys);
}
else
{
tuple = systable_getnext(pCtx->cq_sysScan);
}
if (HeapTupleIsValid(tuple))
{
bool isnull;
Datum d;
if (pFetchcount)
*pFetchcount = 1;
d = caql_getattr_internal(pCtx, tuple, pchn->attnum, &isnull);
if (!isnull)
{
switch (pchn->atttype)
{
case NAMEOID:
result = DatumGetCString(DirectFunctionCall1(nameout, d));
break;
case TEXTOID:
result = DatumGetCString(DirectFunctionCall1(textout, d));
break;
default:
elog(ERROR, "column not a cstring: %s\nfile: %s, line %d",
caql_str, filenam, lineno);
}
}
if (pbIsNull)
*pbIsNull = isnull;
} /* end HeapTupleIsValid */
if (pCtx->cq_usesyscache)
{
if (HeapTupleIsValid(tuple))
ReleaseSysCache(tuple);
}
else
{
if (pFetchcount && HeapTupleIsValid(tuple))
{
if (HeapTupleIsValid(systable_getnext(pCtx->cq_sysScan)))
{
*pFetchcount = 2;
}
}
systable_endscan(pCtx->cq_sysScan);
}
caql_heapclose(pCtx);
return (result);
} /* end caql_getcstring_plus */
/* ----------------------------------------------------------------
* caql_getoid_plus()
* Return an oid column from the first tuple and end the scan.
* Note: this works for regproc columns as well, but you should cast
* the output as RegProcedure.
* ----------------------------------------------------------------
*/
Oid caql_getoid_plus(cqContext *pCtx0, int *pFetchcount,
bool *pbIsNull, cq_list *pcql)
{
const char *caql_str = pcql->caqlStr;
const char *filenam = pcql->filename;
int lineno = pcql->lineno;
struct caql_hash_cookie *pchn = cq_lookup(caql_str, strlen(caql_str), pcql);
cqContext *pCtx;
cqContext cqc;
HeapTuple tuple;
Oid result = InvalidOid;
if (NULL == pchn)
elog(ERROR, "invalid caql string: %s\nfile: %s, line %d",
caql_str, filenam, lineno);
Assert(!pchn->bInsert); /* INSERT not allowed */
/* use the provided context, or provide a clean local ctx */
if (pCtx0)
pCtx = pCtx0;
else
pCtx = cqclr(&cqc);
pCtx = caql_switch(pchn, pCtx, pcql);
/* NOTE: caql_switch frees the pcql */
if (pFetchcount)
*pFetchcount = 0;
if (pbIsNull)
*pbIsNull = true;
/* use the SysCache */
if (pCtx->cq_usesyscache)
{
tuple = SearchSysCacheKeyArray(pCtx->cq_cacheId,
pCtx->cq_NumKeys,
pCtx->cq_cacheKeys);
}
else
{
tuple = systable_getnext(pCtx->cq_sysScan);
}
if (HeapTupleIsValid(tuple))
{
if (pFetchcount)
*pFetchcount = 1;
/* if attnum not set, (InvalidAttrNumber == 0)
* use tuple oid, else extract oid from column
* (includes ObjectIdAttributeNumber == -2)
*/
if (pchn->attnum <= InvalidAttrNumber)
{
if (pbIsNull)
*pbIsNull = false;
result = HeapTupleGetOid(tuple);
}
else /* find oid column */
{
bool isnull;
Datum d = caql_getattr_internal(pCtx, tuple, pchn->attnum,
&isnull);
if (!isnull)
{
switch (pchn->atttype)
{
case OIDOID:
case REGPROCOID:
result = DatumGetObjectId(d);
break;
default:
elog(ERROR, "column not an oid: %s\nfile: %s, line %d",
caql_str, filenam, lineno);
}
}
if (pbIsNull)
*pbIsNull = isnull;
}
} /* end HeapTupleIsValid */
if (pCtx->cq_usesyscache)
{
if (HeapTupleIsValid(tuple))
ReleaseSysCache(tuple);
}
else
{
if (pFetchcount && HeapTupleIsValid(tuple))
{
if (HeapTupleIsValid(systable_getnext(pCtx->cq_sysScan)))
{
*pFetchcount = 2;
}
}
systable_endscan(pCtx->cq_sysScan);
}
caql_heapclose(pCtx);
return (result);
} /* end caql_getoid_plus */
