+++ /dev/null
-/*
- * Integer array aggregator / enumerator
- *
- * Mark L. Woodward
- * DMN Digital Music Network.
- * www.dmn.com
- *
- * $PostgreSQL: pgsql/contrib/intagg/int_aggregate.c,v 1.27 2008/05/12 00:00:42 alvherre Exp $
- *
- * Copyright (C) Digital Music Network
- * December 20, 2001
- *
- * This file is the property of the Digital Music Network (DMN).
- * It is being made available to users of the PostgreSQL system
- * under the BSD license.
- */
-#include "postgres.h"
-
-#include <ctype.h>
-#include <sys/types.h>
-
-#include "access/xact.h"
-#include "catalog/indexing.h"
-#include "catalog/pg_proc.h"
-#include "catalog/pg_type.h"
-#include "executor/executor.h"
-#include "fmgr.h"
-#include "miscadmin.h"
-#include "utils/array.h"
-#include "utils/builtins.h"
-#include "utils/memutils.h"
-#include "utils/syscache.h"
-#include "utils/lsyscache.h"
-
-PG_MODULE_MAGIC;
-
-/*
- * This is actually a postgres version of a one dimensional array.
- * We cheat a little by using the lower-bound field as an indicator
- * of the physically allocated size, while the dimensionality is the
- * count of items accumulated so far.
- */
-typedef struct
-{
- ArrayType a;
- int items;
- int lower;
- int4 array[1];
-} PGARRAY;
-
-/* This is used to keep track of our position during enumeration */
-typedef struct callContext
-{
- PGARRAY *p;
- int num;
- int flags;
-} CTX;
-
-#define TOASTED 1
-#define START_NUM 8 /* initial size of arrays */
-#define PGARRAY_SIZE(n) (sizeof(PGARRAY) + (((n)-1)*sizeof(int4)))
-
-static PGARRAY *GetPGArray(PGARRAY * p, AggState *aggstate, bool fAdd);
-static PGARRAY *ShrinkPGArray(PGARRAY * p);
-
-Datum int_agg_state(PG_FUNCTION_ARGS);
-Datum int_agg_final_array(PG_FUNCTION_ARGS);
-Datum int_enum(PG_FUNCTION_ARGS);
-
-PG_FUNCTION_INFO_V1(int_agg_state);
-PG_FUNCTION_INFO_V1(int_agg_final_array);
-PG_FUNCTION_INFO_V1(int_enum);
-
-/*
- * Manage the allocation state of the array
- *
- * Note that the array needs to be in a reasonably long-lived context,
- * ie the Agg node's aggcontext.
- */
-static PGARRAY *
-GetPGArray(PGARRAY * p, AggState *aggstate, bool fAdd)
-{
- if (!p)
- {
- /* New array */
- int cb = PGARRAY_SIZE(START_NUM);
-
- p = (PGARRAY *) MemoryContextAlloc(aggstate->aggcontext, cb);
- SET_VARSIZE(p, cb);
- p->a.ndim = 1;
- p->a.dataoffset = 0; /* we don't support nulls, for now */
- p->a.elemtype = INT4OID;
- p->items = 0;
- p->lower = START_NUM;
- }
- else if (fAdd)
- {
- /* Ensure array has space for another item */
- if (p->items >= p->lower)
- {
- PGARRAY *pn;
- int n = p->lower * 2;
- int cbNew = PGARRAY_SIZE(n);
-
- pn = (PGARRAY *) MemoryContextAlloc(aggstate->aggcontext, cbNew);
- memcpy(pn, p, VARSIZE(p));
- SET_VARSIZE(pn, cbNew);
- pn->lower = n;
- /* do not pfree(p), because nodeAgg.c will */
- p = pn;
- }
- }
- return p;
-}
-
-/*
- * Shrinks the array to its actual size and moves it into the standard
- * memory allocation context
- */
-static PGARRAY *
-ShrinkPGArray(PGARRAY * p)
-{
- PGARRAY *pnew;
-
- /* get target size */
- int cb = PGARRAY_SIZE(p->items);
-
- /* use current transaction context */
- pnew = palloc(cb);
- memcpy(pnew, p, cb);
-
- /* fix up the fields in the new array to match normal conventions */
- SET_VARSIZE(pnew, cb);
- pnew->lower = 1;
-
- /* do not pfree(p), because nodeAgg.c will */
-
- return pnew;
-}
-
-/* Called for each iteration during an aggregate function */
-Datum
-int_agg_state(PG_FUNCTION_ARGS)
-{
- PGARRAY *state;
- PGARRAY *p;
-
- /*
- * As of PG 8.1 we can actually verify that we are being used as an
- * aggregate function, and so it is safe to scribble on our left input.
- */
- if (!(fcinfo->context && IsA(fcinfo->context, AggState)))
- elog(ERROR, "int_agg_state may only be used as an aggregate");
-
- if (PG_ARGISNULL(0))
- state = NULL; /* first time through */
- else
- state = (PGARRAY *) PG_GETARG_POINTER(0);
- p = GetPGArray(state, (AggState *) fcinfo->context, true);
-
- if (!PG_ARGISNULL(1))
- {
- int4 value = PG_GETARG_INT32(1);
-
- if (!p) /* internal error */
- elog(ERROR, "no aggregate storage");
- else if (p->items >= p->lower) /* internal error */
- elog(ERROR, "aggregate storage too small");
- else
- p->array[p->items++] = value;
- }
- PG_RETURN_POINTER(p);
-}
-
-/*
- * This is the final function used for the integer aggregator. It returns all
- * the integers collected as a one dimensional integer array
- */
-Datum
-int_agg_final_array(PG_FUNCTION_ARGS)
-{
- PGARRAY *state;
- PGARRAY *p;
- PGARRAY *pnew;
-
- /*
- * As of PG 8.1 we can actually verify that we are being used as an
- * aggregate function, and so it is safe to scribble on our left input.
- */
- if (!(fcinfo->context && IsA(fcinfo->context, AggState)))
- elog(ERROR, "int_agg_final_array may only be used as an aggregate");
-
- if (PG_ARGISNULL(0))
- state = NULL; /* zero items in aggregation */
- else
- state = (PGARRAY *) PG_GETARG_POINTER(0);
- p = GetPGArray(state, (AggState *) fcinfo->context, false);
-
- pnew = ShrinkPGArray(p);
- PG_RETURN_POINTER(pnew);
-}
-
-/*
- * This function accepts an array, and returns one item for each entry in the
- * array
- */
-Datum
-int_enum(PG_FUNCTION_ARGS)
-{
- PGARRAY *p = (PGARRAY *) PG_GETARG_POINTER(0);
- CTX *pc;
- ReturnSetInfo *rsi = (ReturnSetInfo *) fcinfo->resultinfo;
-
- if (!rsi || !IsA(rsi, ReturnSetInfo))
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("int_enum called in context that cannot accept a set")));
-
- if (!p)
- {
- elog(WARNING, "no data sent");
- PG_RETURN_NULL();
- }
-
- if (!fcinfo->flinfo->fn_extra)
- {
- /* Allocate working state */
- MemoryContext oldcontext;
-
- oldcontext = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
-
- pc = (CTX *) palloc(sizeof(CTX));
-
- /* Don't copy attribute if you don't need to */
- if (VARATT_IS_EXTENDED(p))
- {
- /* Toasted!!! */
- pc->p = (PGARRAY *) PG_DETOAST_DATUM_COPY(p);
- pc->flags = TOASTED;
- }
- else
- {
- /* Untoasted */
- pc->p = p;
- pc->flags = 0;
- }
- /* Now that we have a detoasted array, verify dimensions */
- /* We'll treat a zero-D array as empty, below */
- if (pc->p->a.ndim > 1)
- elog(ERROR, "int_enum only accepts 1-D arrays");
- pc->num = 0;
- fcinfo->flinfo->fn_extra = (void *) pc;
- MemoryContextSwitchTo(oldcontext);
- }
- else
- /* use existing working state */
- pc = (CTX *) fcinfo->flinfo->fn_extra;
-
- /* Are we done yet? */
- if (pc->p->a.ndim < 1 || pc->num >= pc->p->items)
- {
- /* We are done */
- if (pc->flags & TOASTED)
- pfree(pc->p);
- pfree(pc);
- fcinfo->flinfo->fn_extra = NULL;
- rsi->isDone = ExprEndResult;
- }
- else
- {
- /* nope, return the next value */
- int val = pc->p->array[pc->num++];
-
- rsi->isDone = ExprMultipleResult;
- PG_RETURN_INT32(val);
- }
- PG_RETURN_NULL();
-}
-/* $PostgreSQL: pgsql/contrib/intagg/int_aggregate.sql.in,v 1.9 2007/11/13 04:24:28 momjian Exp $ */
+/* $PostgreSQL: pgsql/contrib/intagg/int_aggregate.sql,v 1.1 2008/11/14 19:58:45 tgl Exp $ */
-- Adjust this setting to control where the objects get created.
SET search_path = public;
-- Internal function for the aggregate
-- Is called for each item in an aggregation
-CREATE OR REPLACE FUNCTION int_agg_state (int4[], int4)
-RETURNS int4[]
-AS 'MODULE_PATHNAME','int_agg_state'
-LANGUAGE C;
+CREATE OR REPLACE FUNCTION int_agg_state (internal, int4)
+RETURNS internal
+AS 'array_agg_transfn'
+LANGUAGE INTERNAL;
-- Internal function for the aggregate
-- Is called at the end of the aggregation, and returns an array.
-CREATE OR REPLACE FUNCTION int_agg_final_array (int4[])
+CREATE OR REPLACE FUNCTION int_agg_final_array (internal)
RETURNS int4[]
-AS 'MODULE_PATHNAME','int_agg_final_array'
-LANGUAGE C;
+AS 'array_agg_finalfn'
+LANGUAGE INTERNAL;
-- The aggregate function itself
-- uses the above functions to create an array of integers from an aggregation.
CREATE AGGREGATE int_array_aggregate (
BASETYPE = int4,
SFUNC = int_agg_state,
- STYPE = int4[],
+ STYPE = internal,
FINALFUNC = int_agg_final_array
);
-- as a row.
CREATE OR REPLACE FUNCTION int_array_enum(int4[])
RETURNS setof integer
-AS 'MODULE_PATHNAME','int_enum'
-LANGUAGE C IMMUTABLE STRICT;
+AS 'array_unnest'
+LANGUAGE INTERNAL IMMUTABLE STRICT;
-<!-- $PostgreSQL: pgsql/doc/src/sgml/intagg.sgml,v 1.3 2007/12/10 05:32:51 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/intagg.sgml,v 1.4 2008/11/14 19:58:45 tgl Exp $ -->
<sect1 id="intagg">
<title>intagg</title>
<para>
The <filename>intagg</filename> module provides an integer aggregator and an
- enumerator.
+ enumerator. <filename>intagg</filename> is now obsolete, because there
+ are built-in functions that provide a superset of its capabilities.
+ However, the module is still provided as a compatibility wrapper around
+ the built-in functions.
</para>
<sect2>
<function>int_array_aggregate(integer)</>
that produces an integer array
containing exactly the integers it is fed.
- Here is a not-tremendously-useful example:
+ This is a wrapper around <function>array_agg</>,
+ which does the same thing for any array type.
</para>
- <programlisting>
-test=# select int_array_aggregate(i) from
-test-# generate_series(1,10,2) i;
- int_array_aggregate
----------------------
- {1,3,5,7,9}
-(1 row)
- </programlisting>
-
<para>
The enumerator is a function
<function>int_array_enum(integer[])</>
that returns <type>setof integer</>. It is essentially the reverse
operation of the aggregator: given an array of integers, expand it
- into a set of rows. For example,
+ into a set of rows. This is a wrapper around <function>unnest</>,
+ which does the same thing for any array type.
</para>
- <programlisting>
-test=# select * from int_array_enum(array[1,3,5,7,9]);
- int_array_enum
-----------------
- 1
- 3
- 5
- 7
- 9
-(5 rows)
- </programlisting>
-
</sect2>
<sect2>
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