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postgresql/src/include/executor/nodeRecursiveunion.h

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Implement SQL-standard WITH clauses, including WITH RECURSIVE. There are some unimplemented aspects: recursive queries must use UNION ALL (should allow UNION too), and we don't have SEARCH or CYCLE clauses. These might or might not get done for 8.4, but even without them it's a pretty useful feature. There are also a couple of small loose ends and definitional quibbles, which I'll send a memo about to pgsql-hackers shortly. But let's land the patch now so we can get on with other development. Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane
2008-10-04 17:56:55 -04:00
/*-------------------------------------------------------------------------
*
* nodeRecursiveunion.h
*
*
*
Update copyright for the year 2010.
2010-01-02 11:58:17 -05:00
* Portions Copyright (c) 1996-2010, PostgreSQL Global Development Group
Implement SQL-standard WITH clauses, including WITH RECURSIVE. There are some unimplemented aspects: recursive queries must use UNION ALL (should allow UNION too), and we don't have SEARCH or CYCLE clauses. These might or might not get done for 8.4, but even without them it's a pretty useful feature. There are also a couple of small loose ends and definitional quibbles, which I'll send a memo about to pgsql-hackers shortly. But let's land the patch now so we can get on with other development. Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane
2008-10-04 17:56:55 -04:00
* Portions Copyright (c) 1994, Regents of the University of California
*
Make NestLoop plan nodes pass outer-relation variables into their inner relation using the general PARAM_EXEC executor parameter mechanism, rather than the ad-hoc kluge of passing the outer tuple down through ExecReScan. The previous method was hard to understand and could never be extended to handle parameters coming from multiple join levels. This patch doesn't change the set of possible plans nor have any significant performance effect, but it's necessary infrastructure for future generalization of the concept of an inner indexscan plan. ExecReScan's second parameter is now unused, so it's removed.
2010-07-12 13:01:06 -04:00
* $PostgreSQL: pgsql/src/include/executor/nodeRecursiveunion.h,v 1.5 2010/07/12 17:01:06 tgl Exp $
Implement SQL-standard WITH clauses, including WITH RECURSIVE. There are some unimplemented aspects: recursive queries must use UNION ALL (should allow UNION too), and we don't have SEARCH or CYCLE clauses. These might or might not get done for 8.4, but even without them it's a pretty useful feature. There are also a couple of small loose ends and definitional quibbles, which I'll send a memo about to pgsql-hackers shortly. But let's land the patch now so we can get on with other development. Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane
2008-10-04 17:56:55 -04:00
*
*-------------------------------------------------------------------------
*/
#ifndef NODERECURSIVEUNION_H
#define NODERECURSIVEUNION_H
#include "nodes/execnodes.h"
extern RecursiveUnionState *ExecInitRecursiveUnion(RecursiveUnion *node, EState *estate, int eflags);
extern TupleTableSlot *ExecRecursiveUnion(RecursiveUnionState *node);
extern void ExecEndRecursiveUnion(RecursiveUnionState *node);
Make NestLoop plan nodes pass outer-relation variables into their inner relation using the general PARAM_EXEC executor parameter mechanism, rather than the ad-hoc kluge of passing the outer tuple down through ExecReScan. The previous method was hard to understand and could never be extended to handle parameters coming from multiple join levels. This patch doesn't change the set of possible plans nor have any significant performance effect, but it's necessary infrastructure for future generalization of the concept of an inner indexscan plan. ExecReScan's second parameter is now unused, so it's removed.
2010-07-12 13:01:06 -04:00
extern void ExecReScanRecursiveUnion(RecursiveUnionState *node);
Implement SQL-standard WITH clauses, including WITH RECURSIVE. There are some unimplemented aspects: recursive queries must use UNION ALL (should allow UNION too), and we don't have SEARCH or CYCLE clauses. These might or might not get done for 8.4, but even without them it's a pretty useful feature. There are also a couple of small loose ends and definitional quibbles, which I'll send a memo about to pgsql-hackers shortly. But let's land the patch now so we can get on with other development. Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane
2008-10-04 17:56:55 -04:00
#endif /* NODERECURSIVEUNION_H */
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