postgres

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Bruce Momjian 03155dc764 It seems that SPI_prepare() doesn't work well in some cases.

Pawel Pierscionek [pawel@astercity.net] reported about the
following case 1([SQL] drop table in pgsql).
Michael Contzen [mcontzen@dohle.com] reported about the
following case 2(PL/PGSQL bug using aggregates).
You can find it from pgsql-hackers archive.

1. PL/pgSQL can't execute UTILITY commands.
   SPI_prepare() doesn't copy(save) the utilityStmt member of
   Query type nodes,because copyObject() is not implemented
   for nodes of (Create/Destroy etc)Stmt type.

2. Aggregates in PL/pgSQL cause wrong results.

...
   It's a list including Aggreg type nodes which exist in
   TargetList(i.e Aggreg type nodes are common to aggs
   member list and TargetList).
   AFAIC the common pointer is not copied to the same
   pointer by copyObject() function.
   In my patch I reconstruct aggs member node from
   new(copied) Agg type node.
   Is it proper to use set_agg_tlist_references() function to
   reconstruct aggs member node for Agg type nodes ?

Thanks.

Hiroshi Inoue
Inoue@tpf.co.jp

1999-01-21 22:55:41 +00:00

copyfuncs.c

It seems that SPI_prepare() doesn't work well in some cases.

1999-01-21 22:55:41 +00:00

equalfuncs.c

OK, folks, here is the pgindent output.

1998-09-01 04:40:42 +00:00

list.c

OK, folks, here is the pgindent output.

1998-09-01 04:40:42 +00:00

Makefile

Hi,

1998-04-06 00:32:26 +00:00

makefuncs.c

Makefile removal of internal.c.

1998-07-20 20:01:48 +00:00

nodeFuncs.c

Renaming cleanup, no pgindent yet.

1998-09-01 03:29:17 +00:00

nodes.c

Renaming cleanup, no pgindent yet.

1998-09-01 03:29:17 +00:00

outfuncs.c

FOR UPDATE is in parser & rules.

1999-01-21 16:08:55 +00:00

print.c

OK, folks, here is the pgindent output.

1998-09-01 04:40:42 +00:00

read.c

Renaming cleanup, no pgindent yet.

1998-09-01 03:29:17 +00:00

readfuncs.c

FOR UPDATE is in parser & rules.

1999-01-21 16:08:55 +00:00

README

Postgres95 1.01 Distribution - Virgin Sources

1996-07-09 06:22:35 +00:00

README

*******************************************************************************
*                                                                             *
* EXPLANATION OF THE NODE STRUCTURES                                          *
*    - Andrew Yu (11/94)                                                      *
*                                                                             *
* Copyright (c) 1994, Regents of the University of California                 *
*                                                                             *
* $Id: README,v 1.1.1.1 1996/07/09 06:21:32 scrappy Exp $
*                                                                             *
*******************************************************************************

INTRODUCTION

The current node structures are plain old C structures. "Inheritance" is
achieved by convention. No additional functions will be generated. Functions
that manipulate node structures reside in this directory.


FILES IN THIS DIRECTORY

    Node manipulation functions:
	copyfuncs.c	- copying a node
	equalfuncs.c	- comparing a node
	outfuncs.c	- convert a node to ascii representation
	readfuncs.c	- convert ascii representation back to a node
	makefuncs.c	- creator functions for primitive nodes

    Node definitions:
	nodes.h		- define node tags (NodeTag)
	pg_list.h	- generic list 
	primnodes.h	- primitive nodes
	parsenodes.h	- parse tree nodes
	plannodes.h	- plan tree nodes
	relation.h	- inner plan tree nodes
	execnodes.h	- executor nodes
	memnodes.h	- memory nodes


STEPS TO ADD A NODE

Suppose you wana define a node Foo:

1. add a tag (T_Foo) to the enum NodeTag in nodes.h (You may have to
   recompile the whole tree after doing this.)
2. add the structure definition to the appropriate ???nodes.h file. If you
   intend to inherit from, say a Plan node, put Plan as the first field of
   you definition.
3. if you intend to use copyObject, equal, nodeToString or stringToNode,
   add an appropriate function to copyfuncs.c, equalfuncs.c, outfuncs.c
   and readfuncs.c accordingly. (Except for frequently used nodes, don't
   bother writing a creator function in makefuncs.c)


HISTORICAL NOTE

Prior to the current simple C structure definitions, the Node structures 
uses a pseudo-inheritance system which automatically generates creator and
accessor functions. Since every node inherits from LispValue, the whole thing
is a mess. Here's a little anecdote:

    LispValue definition -- class used to support lisp structures
    in C.  This is here because we did not want to totally rewrite
    planner and executor code which depended on lisp structures when
    we ported postgres V1 from lisp to C. -cim 4/23/90