postgresql/src/backend/nodes
Bruce Momjian 01c76f7411 Ok. Updated patch attached.
- domain.patch -> source patch against pgsql in cvs
- drop_domain.sgml and create_domain.sgml -> New doc/src/sgml/ref docs

- dominfo.txt -> basic domain related queries I used for testing
[ ADDED TO /doc]

Enables domains of array elements -> CREATE DOMAIN dom int4[3][2];

Uses a typbasetype column to describe the origin of the domain.

Copies data to attnotnull rather than processing in execMain().

Some documentation differences from earlier.

If this is approved, I'll start working on pg_dump, and a \dD <domain>
option in psql, and regression tests.  I don't really feel like doing
those until the system table structure settles for pg_type.


CHECKS when added, will also be copied to to the table attributes.  FK
Constraints (if I ever figure out how) will be done similarly.  Both
will lbe handled by MergeDomainAttributes() which is called shortly
before MergeAttributes().

Rod Taylor
2002-03-06 20:35:02 +00:00
..
copyfuncs.c Ok. Updated patch attached. 2002-03-06 20:35:02 +00:00
equalfuncs.c Ok. Updated patch attached. 2002-03-06 20:35:02 +00:00
list.c pgindent run. Make it all clean. 2001-03-22 04:01:46 +00:00
Makefile Fix relative path references so that make knowns which dependencies refer 2000-08-31 16:12:35 +00:00
makefuncs.c pgindent run. Make it all clean. 2001-03-22 04:01:46 +00:00
nodeFuncs.c Another pgindent run. Fixes enum indenting, and improves #endif 2001-10-28 06:26:15 +00:00
nodes.c Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group. 2001-01-24 19:43:33 +00:00
outfuncs.c Change made to elog: 2002-03-06 06:10:59 +00:00
print.c MIN() -> Min, fixes compile problem. 2001-12-20 02:39:26 +00:00
read.c pgindent run on all C files. Java run to follow. initdb/regression 2001-10-25 05:50:21 +00:00
readfuncs.c Second thoughts dept: arrange to cache mergejoin scan selectivity 2002-03-01 06:01:20 +00:00
README Postgres95 1.01 Distribution - Virgin Sources 1996-07-09 06:22:35 +00:00

*******************************************************************************
*                                                                             *
* 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