-<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.448 2008/10/03 07:33:08 heikki Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/func.sgml,v 1.449 2008/10/13 16:25:19 tgl Exp $ -->
<chapter id="functions">
<title>Functions and Operators</title>
be either true or false, never null.
</para>
+ <note>
+ <para>
+ The SQL specification requires row-wise comparison to return NULL if the
+ result depends on comparing two NULL values or a NULL and a non-NULL.
+ <productname>PostgreSQL</productname> does this only when comparing the
+ results of two row constructors or comparing a row constructor to the
+ output of a subquery (as in <xref linkend="functions-subquery">).
+ In other contexts where two composite-type values are compared, two
+ NULL field values are considered equal, and a NULL is considered larger
+ than a non-NULL. This is necessary in order to have consistent sorting
+ and indexing behavior for composite types.
+ </para>
+ </note>
+
</sect2>
</sect1>
-<!-- $PostgreSQL: pgsql/doc/src/sgml/queries.sgml,v 1.47 2008/10/07 19:27:03 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/queries.sgml,v 1.48 2008/10/13 16:25:19 tgl Exp $ -->
<chapter id="queries">
<title>Queries</title>
the recursive part of the query will eventually return no tuples,
or else the query will loop indefinitely. Sometimes, using
<literal>UNION</> instead of <literal>UNION ALL</> can accomplish this
- by discarding rows that duplicate previous output rows; this catches
- cycles that would otherwise repeat. A useful trick for testing queries
+ by discarding rows that duplicate previous output rows. However, often a
+ cycle does not involve output rows that are completely duplicate: it may be
+ necessary to check just one or a few fields to see if the same point has
+ been reached before. The standard method for handling such situations is
+ to compute an array of the already-visited values. For example, consider
+ the following query that searches a table <structname>graph</> using a
+ <structfield>link</> field:
+
+<programlisting>
+WITH RECURSIVE search_graph(id, link, data, depth) AS (
+ SELECT g.id, g.link, g.data, 1
+ FROM graph g
+ UNION ALL
+ SELECT g.id, g.link, g.data, sg.depth + 1
+ FROM graph g, search_graph sg
+ WHERE g.id = sg.link
+)
+SELECT * FROM search_graph;
+</programlisting>
+
+ This query will loop if the <structfield>link</> relationships contain
+ cycles. Because we require a <quote>depth</> output, just changing
+ <literal>UNION ALL</> to <literal>UNION</> would not eliminate the looping.
+ Instead we need to recognize whether we have reached the same row again
+ while following a particular path of links. We add two columns
+ <structfield>path</> and <structfield>cycle</> to the loop-prone query:
+
+<programlisting>
+WITH RECURSIVE search_graph(id, link, data, depth, path, cycle) AS (
+ SELECT g.id, g.link, g.data, 1,
+ ARRAY[g.id],
+ false
+ FROM graph g
+ UNION ALL
+ SELECT g.id, g.link, g.data, sg.depth + 1,
+ path || ARRAY[g.id],
+ g.id = ANY(path)
+ FROM graph g, search_graph sg
+ WHERE g.id = sg.link AND NOT cycle
+)
+SELECT * FROM search_graph;
+</programlisting>
+
+ Aside from preventing cycles, the array value is often useful in its own
+ right as representing the <quote>path</> taken to reach any particular row.
+ </para>
+
+ <para>
+ In the general case where more than one field needs to be checked to
+ recognize a cycle, use an array of rows. For example, if we needed to
+ compare fields <structfield>f1</> and <structfield>f2</>:
+
+<programlisting>
+WITH RECURSIVE search_graph(id, link, data, depth, path, cycle) AS (
+ SELECT g.id, g.link, g.data, 1,
+ ARRAY[ROW(g.f1, g.f2)],
+ false
+ FROM graph g
+ UNION ALL
+ SELECT g.id, g.link, g.data, sg.depth + 1,
+ path || ARRAY[ROW(g.f1, g.f2)],
+ ROW(g.f1, g.f2) = ANY(path)
+ FROM graph g, search_graph sg
+ WHERE g.id = sg.link AND NOT cycle
+)
+SELECT * FROM search_graph;
+</programlisting>
+ </para>
+
+ <tip>
+ <para>
+ Omit the <literal>ROW()</> syntax in the common case where only one field
+ needs to be checked to recognize a cycle. This allows a simple array
+ rather than a composite-type array to be used, gaining efficiency.
+ </para>
+ </tip>
+
+ <para>
+ A helpful trick for testing queries
when you are not certain if they might loop is to place a <literal>LIMIT</>
in the parent query. For example, this query would loop forever without
the <literal>LIMIT</>:
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/commands/indexcmds.c,v 1.179 2008/08/25 22:42:32 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/commands/indexcmds.c,v 1.180 2008/10/13 16:25:19 tgl Exp $
*
*-------------------------------------------------------------------------
*/
atttype = attform->atttypid;
ReleaseSysCache(atttuple);
}
- else if (attribute->expr && IsA(attribute->expr, Var))
+ else if (attribute->expr && IsA(attribute->expr, Var) &&
+ ((Var *) attribute->expr)->varattno != InvalidAttrNumber)
{
/* Tricky tricky, he wrote (column) ... treat as simple attr */
Var *var = (Var *) attribute->expr;
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.168 2008/10/06 17:39:26 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.169 2008/10/13 16:25:19 tgl Exp $
*
*-------------------------------------------------------------------------
*/
CoercionContext ccontext,
CoercionForm cformat,
int location);
+static bool is_complex_array(Oid typid);
/*
/* NB: we do NOT want a RelabelType here */
return node;
}
+#ifdef NOT_USED
+ if (inputTypeId == RECORDARRAYOID &&
+ is_complex_array(targetTypeId))
+ {
+ /* Coerce record[] to a specific complex array type */
+ /* not implemented yet ... */
+ }
+#endif
+ if (targetTypeId == RECORDARRAYOID &&
+ is_complex_array(inputTypeId))
+ {
+ /* Coerce a specific complex array type to record[] */
+ /* NB: we do NOT want a RelabelType here */
+ return node;
+ }
if (typeInheritsFrom(inputTypeId, targetTypeId))
{
/*
ISCOMPLEX(inputTypeId))
continue;
+#ifdef NOT_USED /* not implemented yet */
+ /*
+ * If input is record[] and target is a composite array type,
+ * assume we can coerce (may need tighter checking here)
+ */
+ if (inputTypeId == RECORDARRAYOID &&
+ is_complex_array(targetTypeId))
+ continue;
+#endif
+
+ /*
+ * If input is a composite array type and target is record[], accept
+ */
+ if (targetTypeId == RECORDARRAYOID &&
+ is_complex_array(inputTypeId))
+ continue;
+
/*
* If input is a class type that inherits from target, accept
*/
* invokable, no-function-needed pg_cast entry. Also, a domain is always
* binary-coercible to its base type, though *not* vice versa (in the other
* direction, one must apply domain constraint checks before accepting the
- * value as legitimate). We also need to special-case the polymorphic
- * ANYARRAY type.
+ * value as legitimate). We also need to special-case various polymorphic
+ * types.
*
* This function replaces IsBinaryCompatible(), which was an inherently
* symmetric test. Since the pg_cast entries aren't necessarily symmetric,
if (type_is_enum(srctype))
return true;
+ /* Also accept any composite type as coercible to RECORD */
+ if (targettype == RECORDOID)
+ if (ISCOMPLEX(srctype))
+ return true;
+
+ /* Also accept any composite array type as coercible to RECORD[] */
+ if (targettype == RECORDARRAYOID)
+ if (is_complex_array(srctype))
+ return true;
+
/* Else look in pg_cast */
tuple = SearchSysCache(CASTSOURCETARGET,
ObjectIdGetDatum(srctype),
return result;
}
+
+/*
+ * is_complex_array
+ * Is this type an array of composite?
+ *
+ * Note: this will not return true for record[]; check for RECORDARRAYOID
+ * separately if needed.
+ */
+static bool
+is_complex_array(Oid typid)
+{
+ Oid elemtype = get_element_type(typid);
+
+ return (OidIsValid(elemtype) && ISCOMPLEX(elemtype));
+}
/*-------------------------------------------------------------------------
*
* rowtypes.c
- * I/O functions for generic composite types.
+ * I/O and comparison functions for generic composite types.
*
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/utils/adt/rowtypes.c,v 1.21 2008/05/12 00:00:51 alvherre Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/rowtypes.c,v 1.22 2008/10/13 16:25:19 tgl Exp $
*
*-------------------------------------------------------------------------
*/
ColumnIOData columns[1]; /* VARIABLE LENGTH ARRAY */
} RecordIOData;
+/*
+ * structure to cache metadata needed for record comparison
+ */
+typedef struct ColumnCompareData
+{
+ TypeCacheEntry *typentry; /* has everything we need, actually */
+} ColumnCompareData;
+
+typedef struct RecordCompareData
+{
+ int ncolumns; /* allocated length of columns[] */
+ Oid record1_type;
+ int32 record1_typmod;
+ Oid record2_type;
+ int32 record2_typmod;
+ ColumnCompareData columns[1]; /* VARIABLE LENGTH ARRAY */
+} RecordCompareData;
+
/*
* record_in - input routine for any composite type.
PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}
+
+
+/*
+ * record_cmp()
+ * Internal comparison function for records.
+ *
+ * Returns -1, 0 or 1
+ *
+ * Do not assume that the two inputs are exactly the same record type;
+ * for instance we might be comparing an anonymous ROW() construct against a
+ * named composite type. We will compare as long as they have the same number
+ * of non-dropped columns of the same types.
+ */
+static int
+record_cmp(FunctionCallInfo fcinfo)
+{
+ HeapTupleHeader record1 = PG_GETARG_HEAPTUPLEHEADER(0);
+ HeapTupleHeader record2 = PG_GETARG_HEAPTUPLEHEADER(1);
+ int result = 0;
+ Oid tupType1;
+ Oid tupType2;
+ int32 tupTypmod1;
+ int32 tupTypmod2;
+ TupleDesc tupdesc1;
+ TupleDesc tupdesc2;
+ HeapTupleData tuple1;
+ HeapTupleData tuple2;
+ int ncolumns1;
+ int ncolumns2;
+ RecordCompareData *my_extra;
+ int ncols;
+ Datum *values1;
+ Datum *values2;
+ bool *nulls1;
+ bool *nulls2;
+ int i1;
+ int i2;
+ int j;
+
+ /* Extract type info from the tuples */
+ tupType1 = HeapTupleHeaderGetTypeId(record1);
+ tupTypmod1 = HeapTupleHeaderGetTypMod(record1);
+ tupdesc1 = lookup_rowtype_tupdesc(tupType1, tupTypmod1);
+ ncolumns1 = tupdesc1->natts;
+ tupType2 = HeapTupleHeaderGetTypeId(record2);
+ tupTypmod2 = HeapTupleHeaderGetTypMod(record2);
+ tupdesc2 = lookup_rowtype_tupdesc(tupType2, tupTypmod2);
+ ncolumns2 = tupdesc2->natts;
+
+ /* Build temporary HeapTuple control structures */
+ tuple1.t_len = HeapTupleHeaderGetDatumLength(record1);
+ ItemPointerSetInvalid(&(tuple1.t_self));
+ tuple1.t_tableOid = InvalidOid;
+ tuple1.t_data = record1;
+ tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
+ ItemPointerSetInvalid(&(tuple2.t_self));
+ tuple2.t_tableOid = InvalidOid;
+ tuple2.t_data = record2;
+
+ /*
+ * We arrange to look up the needed comparison info just once per series
+ * of calls, assuming the record types don't change underneath us.
+ */
+ ncols = Max(ncolumns1, ncolumns2);
+ my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+ if (my_extra == NULL ||
+ my_extra->ncolumns < ncols)
+ {
+ fcinfo->flinfo->fn_extra =
+ MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+ sizeof(RecordCompareData) - sizeof(ColumnCompareData)
+ + ncols * sizeof(ColumnCompareData));
+ my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+ my_extra->ncolumns = ncols;
+ my_extra->record1_type = InvalidOid;
+ my_extra->record1_typmod = 0;
+ my_extra->record2_type = InvalidOid;
+ my_extra->record2_typmod = 0;
+ }
+
+ if (my_extra->record1_type != tupType1 ||
+ my_extra->record1_typmod != tupTypmod1 ||
+ my_extra->record2_type != tupType2 ||
+ my_extra->record2_typmod != tupTypmod2)
+ {
+ MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
+ my_extra->record1_type = tupType1;
+ my_extra->record1_typmod = tupTypmod1;
+ my_extra->record2_type = tupType2;
+ my_extra->record2_typmod = tupTypmod2;
+ }
+
+ /* Break down the tuples into fields */
+ values1 = (Datum *) palloc(ncolumns1 * sizeof(Datum));
+ nulls1 = (bool *) palloc(ncolumns1 * sizeof(bool));
+ heap_deform_tuple(&tuple1, tupdesc1, values1, nulls1);
+ values2 = (Datum *) palloc(ncolumns2 * sizeof(Datum));
+ nulls2 = (bool *) palloc(ncolumns2 * sizeof(bool));
+ heap_deform_tuple(&tuple2, tupdesc2, values2, nulls2);
+
+ /*
+ * Scan corresponding columns, allowing for dropped columns in different
+ * places in the two rows. i1 and i2 are physical column indexes,
+ * j is the logical column index.
+ */
+ i1 = i2 = j = 0;
+ while (i1 < ncolumns1 || i2 < ncolumns2)
+ {
+ TypeCacheEntry *typentry;
+ FunctionCallInfoData locfcinfo;
+ int32 cmpresult;
+
+ /*
+ * Skip dropped columns
+ */
+ if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
+ {
+ i1++;
+ continue;
+ }
+ if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
+ {
+ i2++;
+ continue;
+ }
+ if (i1 >= ncolumns1 || i2 >= ncolumns2)
+ break; /* we'll deal with mismatch below loop */
+
+ /*
+ * Have two matching columns, they must be same type
+ */
+ if (tupdesc1->attrs[i1]->atttypid !=
+ tupdesc2->attrs[i2]->atttypid)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("cannot compare dissimilar column types %s and %s at record column %d",
+ format_type_be(tupdesc1->attrs[i1]->atttypid),
+ format_type_be(tupdesc2->attrs[i2]->atttypid),
+ j+1)));
+
+ /*
+ * Lookup the comparison function if not done already
+ */
+ typentry = my_extra->columns[j].typentry;
+ if (typentry == NULL ||
+ typentry->type_id != tupdesc1->attrs[i1]->atttypid)
+ {
+ typentry = lookup_type_cache(tupdesc1->attrs[i1]->atttypid,
+ TYPECACHE_CMP_PROC_FINFO);
+ if (!OidIsValid(typentry->cmp_proc_finfo.fn_oid))
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_FUNCTION),
+ errmsg("could not identify a comparison function for type %s",
+ format_type_be(typentry->type_id))));
+ my_extra->columns[j].typentry = typentry;
+ }
+
+ /*
+ * We consider two NULLs equal; NULL > not-NULL.
+ */
+ if (!nulls1[i1] || !nulls2[i2])
+ {
+ if (nulls1[i1])
+ {
+ /* arg1 is greater than arg2 */
+ result = 1;
+ break;
+ }
+ if (nulls2[i2])
+ {
+ /* arg1 is less than arg2 */
+ result = -1;
+ break;
+ }
+
+ /* Compare the pair of elements */
+ InitFunctionCallInfoData(locfcinfo, &typentry->cmp_proc_finfo, 2,
+ NULL, NULL);
+ locfcinfo.arg[0] = values1[i1];
+ locfcinfo.arg[1] = values2[i2];
+ locfcinfo.argnull[0] = false;
+ locfcinfo.argnull[1] = false;
+ locfcinfo.isnull = false;
+ cmpresult = DatumGetInt32(FunctionCallInvoke(&locfcinfo));
+
+ if (cmpresult < 0)
+ {
+ /* arg1 is less than arg2 */
+ result = -1;
+ break;
+ }
+ else if (cmpresult > 0)
+ {
+ /* arg1 is greater than arg2 */
+ result = 1;
+ break;
+ }
+ }
+
+ /* equal, so continue to next column */
+ i1++, i2++, j++;
+ }
+
+ /*
+ * If we didn't break out of the loop early, check for column count
+ * mismatch. (We do not report such mismatch if we found unequal
+ * column values; is that a feature or a bug?)
+ */
+ if (result == 0)
+ {
+ if (i1 != ncolumns1 || i2 != ncolumns2)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("cannot compare record types with different numbers of columns")));
+ }
+
+ pfree(values1);
+ pfree(nulls1);
+ pfree(values2);
+ pfree(nulls2);
+ ReleaseTupleDesc(tupdesc1);
+ ReleaseTupleDesc(tupdesc2);
+
+ /* Avoid leaking memory when handed toasted input. */
+ PG_FREE_IF_COPY(record1, 0);
+ PG_FREE_IF_COPY(record2, 1);
+
+ return result;
+}
+
+/*
+ * record_eq :
+ * compares two records for equality
+ * result :
+ * returns true if the records are equal, false otherwise.
+ *
+ * Note: we do not use record_cmp here, since equality may be meaningful in
+ * datatypes that don't have a total ordering (and hence no btree support).
+ */
+Datum
+record_eq(PG_FUNCTION_ARGS)
+{
+ HeapTupleHeader record1 = PG_GETARG_HEAPTUPLEHEADER(0);
+ HeapTupleHeader record2 = PG_GETARG_HEAPTUPLEHEADER(1);
+ bool result = true;
+ Oid tupType1;
+ Oid tupType2;
+ int32 tupTypmod1;
+ int32 tupTypmod2;
+ TupleDesc tupdesc1;
+ TupleDesc tupdesc2;
+ HeapTupleData tuple1;
+ HeapTupleData tuple2;
+ int ncolumns1;
+ int ncolumns2;
+ RecordCompareData *my_extra;
+ int ncols;
+ Datum *values1;
+ Datum *values2;
+ bool *nulls1;
+ bool *nulls2;
+ int i1;
+ int i2;
+ int j;
+
+ /* Extract type info from the tuples */
+ tupType1 = HeapTupleHeaderGetTypeId(record1);
+ tupTypmod1 = HeapTupleHeaderGetTypMod(record1);
+ tupdesc1 = lookup_rowtype_tupdesc(tupType1, tupTypmod1);
+ ncolumns1 = tupdesc1->natts;
+ tupType2 = HeapTupleHeaderGetTypeId(record2);
+ tupTypmod2 = HeapTupleHeaderGetTypMod(record2);
+ tupdesc2 = lookup_rowtype_tupdesc(tupType2, tupTypmod2);
+ ncolumns2 = tupdesc2->natts;
+
+ /* Build temporary HeapTuple control structures */
+ tuple1.t_len = HeapTupleHeaderGetDatumLength(record1);
+ ItemPointerSetInvalid(&(tuple1.t_self));
+ tuple1.t_tableOid = InvalidOid;
+ tuple1.t_data = record1;
+ tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
+ ItemPointerSetInvalid(&(tuple2.t_self));
+ tuple2.t_tableOid = InvalidOid;
+ tuple2.t_data = record2;
+
+ /*
+ * We arrange to look up the needed comparison info just once per series
+ * of calls, assuming the record types don't change underneath us.
+ */
+ ncols = Max(ncolumns1, ncolumns2);
+ my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+ if (my_extra == NULL ||
+ my_extra->ncolumns < ncols)
+ {
+ fcinfo->flinfo->fn_extra =
+ MemoryContextAlloc(fcinfo->flinfo->fn_mcxt,
+ sizeof(RecordCompareData) - sizeof(ColumnCompareData)
+ + ncols * sizeof(ColumnCompareData));
+ my_extra = (RecordCompareData *) fcinfo->flinfo->fn_extra;
+ my_extra->ncolumns = ncols;
+ my_extra->record1_type = InvalidOid;
+ my_extra->record1_typmod = 0;
+ my_extra->record2_type = InvalidOid;
+ my_extra->record2_typmod = 0;
+ }
+
+ if (my_extra->record1_type != tupType1 ||
+ my_extra->record1_typmod != tupTypmod1 ||
+ my_extra->record2_type != tupType2 ||
+ my_extra->record2_typmod != tupTypmod2)
+ {
+ MemSet(my_extra->columns, 0, ncols * sizeof(ColumnCompareData));
+ my_extra->record1_type = tupType1;
+ my_extra->record1_typmod = tupTypmod1;
+ my_extra->record2_type = tupType2;
+ my_extra->record2_typmod = tupTypmod2;
+ }
+
+ /* Break down the tuples into fields */
+ values1 = (Datum *) palloc(ncolumns1 * sizeof(Datum));
+ nulls1 = (bool *) palloc(ncolumns1 * sizeof(bool));
+ heap_deform_tuple(&tuple1, tupdesc1, values1, nulls1);
+ values2 = (Datum *) palloc(ncolumns2 * sizeof(Datum));
+ nulls2 = (bool *) palloc(ncolumns2 * sizeof(bool));
+ heap_deform_tuple(&tuple2, tupdesc2, values2, nulls2);
+
+ /*
+ * Scan corresponding columns, allowing for dropped columns in different
+ * places in the two rows. i1 and i2 are physical column indexes,
+ * j is the logical column index.
+ */
+ i1 = i2 = j = 0;
+ while (i1 < ncolumns1 || i2 < ncolumns2)
+ {
+ TypeCacheEntry *typentry;
+ FunctionCallInfoData locfcinfo;
+ bool oprresult;
+
+ /*
+ * Skip dropped columns
+ */
+ if (i1 < ncolumns1 && tupdesc1->attrs[i1]->attisdropped)
+ {
+ i1++;
+ continue;
+ }
+ if (i2 < ncolumns2 && tupdesc2->attrs[i2]->attisdropped)
+ {
+ i2++;
+ continue;
+ }
+ if (i1 >= ncolumns1 || i2 >= ncolumns2)
+ break; /* we'll deal with mismatch below loop */
+
+ /*
+ * Have two matching columns, they must be same type
+ */
+ if (tupdesc1->attrs[i1]->atttypid !=
+ tupdesc2->attrs[i2]->atttypid)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("cannot compare dissimilar column types %s and %s at record column %d",
+ format_type_be(tupdesc1->attrs[i1]->atttypid),
+ format_type_be(tupdesc2->attrs[i2]->atttypid),
+ j+1)));
+
+ /*
+ * Lookup the equality function if not done already
+ */
+ typentry = my_extra->columns[j].typentry;
+ if (typentry == NULL ||
+ typentry->type_id != tupdesc1->attrs[i1]->atttypid)
+ {
+ typentry = lookup_type_cache(tupdesc1->attrs[i1]->atttypid,
+ 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(typentry->type_id))));
+ my_extra->columns[j].typentry = typentry;
+ }
+
+ /*
+ * We consider two NULLs equal; NULL > not-NULL.
+ */
+ if (!nulls1[i1] || !nulls2[i2])
+ {
+ if (nulls1[i1] || nulls2[i2])
+ {
+ result = false;
+ break;
+ }
+
+ /* Compare the pair of elements */
+ InitFunctionCallInfoData(locfcinfo, &typentry->eq_opr_finfo, 2,
+ NULL, NULL);
+ locfcinfo.arg[0] = values1[i1];
+ locfcinfo.arg[1] = values2[i2];
+ locfcinfo.argnull[0] = false;
+ locfcinfo.argnull[1] = false;
+ locfcinfo.isnull = false;
+ oprresult = DatumGetBool(FunctionCallInvoke(&locfcinfo));
+ if (!oprresult)
+ {
+ result = false;
+ break;
+ }
+ }
+
+ /* equal, so continue to next column */
+ i1++, i2++, j++;
+ }
+
+ /*
+ * If we didn't break out of the loop early, check for column count
+ * mismatch. (We do not report such mismatch if we found unequal
+ * column values; is that a feature or a bug?)
+ */
+ if (result)
+ {
+ if (i1 != ncolumns1 || i2 != ncolumns2)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("cannot compare record types with different numbers of columns")));
+ }
+
+ pfree(values1);
+ pfree(nulls1);
+ pfree(values2);
+ pfree(nulls2);
+ ReleaseTupleDesc(tupdesc1);
+ ReleaseTupleDesc(tupdesc2);
+
+ /* Avoid leaking memory when handed toasted input. */
+ PG_FREE_IF_COPY(record1, 0);
+ PG_FREE_IF_COPY(record2, 1);
+
+ PG_RETURN_BOOL(result);
+}
+
+Datum
+record_ne(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_BOOL(!DatumGetBool(record_eq(fcinfo)));
+}
+
+Datum
+record_lt(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_BOOL(record_cmp(fcinfo) < 0);
+}
+
+Datum
+record_gt(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_BOOL(record_cmp(fcinfo) > 0);
+}
+
+Datum
+record_le(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_BOOL(record_cmp(fcinfo) <= 0);
+}
+
+Datum
+record_ge(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_BOOL(record_cmp(fcinfo) >= 0);
+}
+
+Datum
+btrecordcmp(PG_FUNCTION_ARGS)
+{
+ PG_RETURN_INT32(record_cmp(fcinfo));
+}
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.496 2008/10/06 17:39:26 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.497 2008/10/13 16:25:19 tgl Exp $
*
*-------------------------------------------------------------------------
*/
*/
/* yyyymmddN */
-#define CATALOG_VERSION_NO 200810063
+#define CATALOG_VERSION_NO 200810131
#endif
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_amop.h,v 1.87 2008/05/27 00:13:09 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_amop.h,v 1.88 2008/10/13 16:25:19 tgl Exp $
*
* NOTES
* the genbki.sh script reads this file and generates .bki
DATA(insert ( 397 2277 2277 4 1075 403 ));
DATA(insert ( 397 2277 2277 5 1073 403 ));
+/*
+ * btree record_ops
+ */
+
+DATA(insert ( 2994 2249 2249 1 2990 403 ));
+DATA(insert ( 2994 2249 2249 2 2992 403 ));
+DATA(insert ( 2994 2249 2249 3 2988 403 ));
+DATA(insert ( 2994 2249 2249 4 2993 403 ));
+DATA(insert ( 2994 2249 2249 5 2991 403 ));
+
/*
* btree uuid_ops
*/
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_amproc.h,v 1.73 2008/05/27 00:13:09 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_amproc.h,v 1.74 2008/10/13 16:25:19 tgl Exp $
*
* NOTES
* the genbki.sh script reads this file and generates .bki
DATA(insert ( 1988 1700 1700 1 1769 ));
DATA(insert ( 1989 26 26 1 356 ));
DATA(insert ( 1991 30 30 1 404 ));
+DATA(insert ( 2994 2249 2249 1 2987 ));
DATA(insert ( 1994 25 25 1 360 ));
DATA(insert ( 1996 1083 1083 1 1107 ));
DATA(insert ( 2000 1266 1266 1 1358 ));
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_opclass.h,v 1.83 2008/09/15 18:43:41 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_opclass.h,v 1.84 2008/10/13 16:25:20 tgl Exp $
*
* NOTES
* the genbki.sh script reads this file and generates .bki
DATA(insert ( 405 oid_ops PGNSP PGUID 1990 26 t 0 ));
DATA(insert ( 403 oidvector_ops PGNSP PGUID 1991 30 t 0 ));
DATA(insert ( 405 oidvector_ops PGNSP PGUID 1992 30 t 0 ));
+DATA(insert ( 403 record_ops PGNSP PGUID 2994 2249 t 0 ));
DATA(insert ( 403 text_ops PGNSP PGUID 1994 25 t 0 ));
DATA(insert ( 405 text_ops PGNSP PGUID 1995 25 t 0 ));
DATA(insert ( 403 time_ops PGNSP PGUID 1996 1083 t 0 ));
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_operator.h,v 1.163 2008/09/19 19:03:40 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_operator.h,v 1.164 2008/10/13 16:25:20 tgl Exp $
*
* NOTES
* the genbki.sh script reads this file and generates .bki
DATA(insert OID = 3762 ( "@@" PGNSP PGUID b f f 25 25 16 0 0 ts_match_tt contsel contjoinsel ));
DATA(insert OID = 3763 ( "@@" PGNSP PGUID b f f 25 3615 16 0 0 ts_match_tq contsel contjoinsel ));
+/* generic record comparison operators */
+DATA(insert OID = 2988 ( "=" PGNSP PGUID b t f 2249 2249 16 2988 2989 record_eq eqsel eqjoinsel ));
+DATA(insert OID = 2989 ( "<>" PGNSP PGUID b f f 2249 2249 16 2989 2988 record_ne neqsel neqjoinsel ));
+DATA(insert OID = 2990 ( "<" PGNSP PGUID b f f 2249 2249 16 2991 2993 record_lt scalarltsel scalarltjoinsel ));
+DATA(insert OID = 2991 ( ">" PGNSP PGUID b f f 2249 2249 16 2990 2992 record_gt scalargtsel scalargtjoinsel ));
+DATA(insert OID = 2992 ( "<=" PGNSP PGUID b f f 2249 2249 16 2993 2991 record_le scalarltsel scalarltjoinsel ));
+DATA(insert OID = 2993 ( ">=" PGNSP PGUID b f f 2249 2249 16 2992 2990 record_ge scalargtsel scalargtjoinsel ));
+
/*
* function prototypes
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_opfamily.h,v 1.9 2008/05/27 00:13:09 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_opfamily.h,v 1.10 2008/10/13 16:25:20 tgl Exp $
*
* NOTES
* the genbki.sh script reads this file and generates .bki
DATA(insert OID = 1990 ( 405 oid_ops PGNSP PGUID ));
DATA(insert OID = 1991 ( 403 oidvector_ops PGNSP PGUID ));
DATA(insert OID = 1992 ( 405 oidvector_ops PGNSP PGUID ));
+DATA(insert OID = 2994 ( 403 record_ops PGNSP PGUID ));
DATA(insert OID = 1994 ( 403 text_ops PGNSP PGUID ));
#define TEXT_BTREE_FAM_OID 1994
DATA(insert OID = 1995 ( 405 text_ops PGNSP PGUID ));
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.518 2008/10/06 13:05:37 mha Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.519 2008/10/13 16:25:20 tgl Exp $
*
* NOTES
* The script catalog/genbki.sh reads this file and generates .bki
DATA(insert OID = 2948 ( txid_visible_in_snapshot PGNSP PGUID 12 1 0 0 f f t f i 2 16 "20 2970" _null_ _null_ _null_ txid_visible_in_snapshot _null_ _null_ _null_ ));
DESCR("is txid visible in snapshot?");
+/* record comparison */
+DATA(insert OID = 2981 ( record_eq PGNSP PGUID 12 1 0 0 f f t f i 2 16 "2249 2249" _null_ _null_ _null_ record_eq _null_ _null_ _null_ ));
+DESCR("record equal");
+DATA(insert OID = 2982 ( record_ne PGNSP PGUID 12 1 0 0 f f t f i 2 16 "2249 2249" _null_ _null_ _null_ record_ne _null_ _null_ _null_ ));
+DESCR("record not equal");
+DATA(insert OID = 2983 ( record_lt PGNSP PGUID 12 1 0 0 f f t f i 2 16 "2249 2249" _null_ _null_ _null_ record_lt _null_ _null_ _null_ ));
+DESCR("record less than");
+DATA(insert OID = 2984 ( record_gt PGNSP PGUID 12 1 0 0 f f t f i 2 16 "2249 2249" _null_ _null_ _null_ record_gt _null_ _null_ _null_ ));
+DESCR("record greater than");
+DATA(insert OID = 2985 ( record_le PGNSP PGUID 12 1 0 0 f f t f i 2 16 "2249 2249" _null_ _null_ _null_ record_le _null_ _null_ _null_ ));
+DESCR("record less than or equal");
+DATA(insert OID = 2986 ( record_ge PGNSP PGUID 12 1 0 0 f f t f i 2 16 "2249 2249" _null_ _null_ _null_ record_ge _null_ _null_ _null_ ));
+DESCR("record greater than or equal");
+DATA(insert OID = 2987 ( btrecordcmp PGNSP PGUID 12 1 0 0 f f t f i 2 23 "2249 2249" _null_ _null_ _null_ btrecordcmp _null_ _null_ _null_ ));
+DESCR("btree less-equal-greater");
+
/*
* Symbolic values for provolatile column: these indicate whether the result
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/pg_type.h,v 1.200 2008/09/25 03:28:56 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/pg_type.h,v 1.201 2008/10/13 16:25:20 tgl Exp $
*
* NOTES
* the genbki.sh script reads this file and generates .bki
* but there is now support for it in records and arrays. Perhaps we should
* just treat it as a regular base type?
*/
-DATA(insert OID = 2249 ( record PGNSP PGUID -1 f p P f t \054 0 0 0 record_in record_out record_recv record_send - - - d x f 0 -1 0 _null_ _null_ ));
+DATA(insert OID = 2249 ( record PGNSP PGUID -1 f p P f t \054 0 0 2287 record_in record_out record_recv record_send - - - d x f 0 -1 0 _null_ _null_ ));
#define RECORDOID 2249
+DATA(insert OID = 2287 ( _record PGNSP PGUID -1 f p P f t \054 0 2249 0 array_in array_out array_recv array_send - - - d x f 0 -1 0 _null_ _null_ ));
+#define RECORDARRAYOID 2287
DATA(insert OID = 2275 ( cstring PGNSP PGUID -2 f p P f t \054 0 0 1263 cstring_in cstring_out cstring_recv cstring_send - - - c p f 0 -1 0 _null_ _null_ ));
#define CSTRINGOID 2275
DATA(insert OID = 2276 ( any PGNSP PGUID 4 t p P f t \054 0 0 0 any_in any_out - - - - - i p f 0 -1 0 _null_ _null_ ));
* Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.323 2008/10/06 20:29:38 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.324 2008/10/13 16:25:20 tgl Exp $
*
*-------------------------------------------------------------------------
*/
extern Datum record_out(PG_FUNCTION_ARGS);
extern Datum record_recv(PG_FUNCTION_ARGS);
extern Datum record_send(PG_FUNCTION_ARGS);
+extern Datum record_eq(PG_FUNCTION_ARGS);
+extern Datum record_ne(PG_FUNCTION_ARGS);
+extern Datum record_lt(PG_FUNCTION_ARGS);
+extern Datum record_gt(PG_FUNCTION_ARGS);
+extern Datum record_le(PG_FUNCTION_ARGS);
+extern Datum record_ge(PG_FUNCTION_ARGS);
+extern Datum btrecordcmp(PG_FUNCTION_ARGS);
/* ruleutils.c */
extern Datum pg_get_ruledef(PG_FUNCTION_ARGS);
ERROR: cannot compare rows of zero length
LINE 1: select ROW() = ROW();
^
+-- Check ability to create arrays of anonymous rowtypes
+select array[ row(1,2), row(3,4), row(5,6) ];
+ array
+---------------------------
+ {"(1,2)","(3,4)","(5,6)"}
+(1 row)
+
+-- Check ability to compare an anonymous row to elements of an array
+select row(1,1.1) = any (array[ row(7,7.7), row(1,1.1), row(0,0.0) ]);
+ ?column?
+----------
+ t
+(1 row)
+
+select row(1,1.1) = any (array[ row(7,7.7), row(1,1.0), row(0,0.0) ]);
+ ?column?
+----------
+ f
+(1 row)
+
3 | 7
(2 rows)
+--
+-- test cycle detection
+--
+create temp table graph( f int, t int, label text );
+insert into graph values
+ (1, 2, 'arc 1 -> 2'),
+ (1, 3, 'arc 1 -> 3'),
+ (2, 3, 'arc 2 -> 3'),
+ (1, 4, 'arc 1 -> 4'),
+ (4, 5, 'arc 4 -> 5'),
+ (5, 1, 'arc 5 -> 1');
+with recursive search_graph(f, t, label, path, cycle) as (
+ select *, array[row(g.f, g.t)], false from graph g
+ union all
+ select g.*, path || array[row(g.f, g.t)], row(g.f, g.t) = any(path)
+ from graph g, search_graph sg
+ where g.f = sg.t and not cycle
+)
+select * from search_graph;
+ f | t | label | path | cycle
+---+---+------------+-------------------------------------------+-------
+ 1 | 2 | arc 1 -> 2 | {"(1,2)"} | f
+ 1 | 3 | arc 1 -> 3 | {"(1,3)"} | f
+ 2 | 3 | arc 2 -> 3 | {"(2,3)"} | f
+ 1 | 4 | arc 1 -> 4 | {"(1,4)"} | f
+ 4 | 5 | arc 4 -> 5 | {"(4,5)"} | f
+ 5 | 1 | arc 5 -> 1 | {"(5,1)"} | f
+ 1 | 2 | arc 1 -> 2 | {"(5,1)","(1,2)"} | f
+ 1 | 3 | arc 1 -> 3 | {"(5,1)","(1,3)"} | f
+ 1 | 4 | arc 1 -> 4 | {"(5,1)","(1,4)"} | f
+ 2 | 3 | arc 2 -> 3 | {"(1,2)","(2,3)"} | f
+ 4 | 5 | arc 4 -> 5 | {"(1,4)","(4,5)"} | f
+ 5 | 1 | arc 5 -> 1 | {"(4,5)","(5,1)"} | f
+ 1 | 2 | arc 1 -> 2 | {"(4,5)","(5,1)","(1,2)"} | f
+ 1 | 3 | arc 1 -> 3 | {"(4,5)","(5,1)","(1,3)"} | f
+ 1 | 4 | arc 1 -> 4 | {"(4,5)","(5,1)","(1,4)"} | f
+ 2 | 3 | arc 2 -> 3 | {"(5,1)","(1,2)","(2,3)"} | f
+ 4 | 5 | arc 4 -> 5 | {"(5,1)","(1,4)","(4,5)"} | f
+ 5 | 1 | arc 5 -> 1 | {"(1,4)","(4,5)","(5,1)"} | f
+ 1 | 2 | arc 1 -> 2 | {"(1,4)","(4,5)","(5,1)","(1,2)"} | f
+ 1 | 3 | arc 1 -> 3 | {"(1,4)","(4,5)","(5,1)","(1,3)"} | f
+ 1 | 4 | arc 1 -> 4 | {"(1,4)","(4,5)","(5,1)","(1,4)"} | t
+ 2 | 3 | arc 2 -> 3 | {"(4,5)","(5,1)","(1,2)","(2,3)"} | f
+ 4 | 5 | arc 4 -> 5 | {"(4,5)","(5,1)","(1,4)","(4,5)"} | t
+ 5 | 1 | arc 5 -> 1 | {"(5,1)","(1,4)","(4,5)","(5,1)"} | t
+ 2 | 3 | arc 2 -> 3 | {"(1,4)","(4,5)","(5,1)","(1,2)","(2,3)"} | f
+(25 rows)
+
--
-- test multiple WITH queries
--
select ROW();
select ROW() IS NULL;
select ROW() = ROW();
+
+-- Check ability to create arrays of anonymous rowtypes
+select array[ row(1,2), row(3,4), row(5,6) ];
+
+-- Check ability to compare an anonymous row to elements of an array
+select row(1,1.1) = any (array[ row(7,7.7), row(1,1.1), row(0,0.0) ]);
+select row(1,1.1) = any (array[ row(7,7.7), row(1,1.0), row(0,0.0) ]);
GROUP BY t1.id
ORDER BY t1.id;
+--
+-- test cycle detection
+--
+create temp table graph( f int, t int, label text );
+
+insert into graph values
+ (1, 2, 'arc 1 -> 2'),
+ (1, 3, 'arc 1 -> 3'),
+ (2, 3, 'arc 2 -> 3'),
+ (1, 4, 'arc 1 -> 4'),
+ (4, 5, 'arc 4 -> 5'),
+ (5, 1, 'arc 5 -> 1');
+
+with recursive search_graph(f, t, label, path, cycle) as (
+ select *, array[row(g.f, g.t)], false from graph g
+ union all
+ select g.*, path || array[row(g.f, g.t)], row(g.f, g.t) = any(path)
+ from graph g, search_graph sg
+ where g.f = sg.t and not cycle
+)
+select * from search_graph;
+
--
-- test multiple WITH queries
--
projects / postgresql / commitdiff