pg_description.h

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/*-------------------------------------------------------------------------
 *
 * pg_description.h
 *    definition of the system "description" relation (pg_description)
 *
 * NOTE: an object is identified by the OID of the row that primarily
 * defines the object, plus the OID of the table that that row appears in.
 * For example, a function is identified by the OID of its pg_proc row
 * plus the pg_class OID of table pg_proc.  This allows unique identification
 * of objects without assuming that OIDs are unique across tables.
 *
 * Since attributes don't have OIDs of their own, we identify an attribute
 * comment by the objoid+classoid of its parent table, plus an "objsubid"
 * giving the attribute column number.  "objsubid" must be zero in a comment
 * for a table itself, so that it is distinct from any column comment.
 * Currently, objsubid is unused and zero for all other kinds of objects,
 * but perhaps it might be useful someday to associate comments with
 * constituent elements of other kinds of objects (arguments of a function,
 * for example).
 *
 *
 * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/catalog/pg_description.h
 *
 * NOTES
 *      the genbki.pl script reads this file and generates .bki
 *      information from the DATA() statements.
 *
 *      XXX do NOT break up DATA() statements into multiple lines!
 *          the scripts are not as smart as you might think...
 *
 *-------------------------------------------------------------------------
 */
#ifndef PG_DESCRIPTION_H
#define PG_DESCRIPTION_H

#include "catalog/genbki.h"

/* ----------------
 *      pg_description definition.  cpp turns this into
 *      typedef struct FormData_pg_description
 * ----------------
 */
#define DescriptionRelationId  2609

CATALOG(pg_description,2609) BKI_WITHOUT_OIDS
{
    Oid         objoid;         /* OID of object itself */
    Oid         classoid;       /* OID of table containing object */
    int32       objsubid;       /* column number, or 0 if not used */

#ifdef CATALOG_VARLEN           /* variable-length fields start here */
    text        description;    /* description of object */
#endif
} FormData_pg_description;

/* ----------------
 *      Form_pg_description corresponds to a pointer to a tuple with
 *      the format of pg_description relation.
 * ----------------
 */
typedef FormData_pg_description *Form_pg_description;

/* ----------------
 *      compiler constants for pg_description
 * ----------------
 */
#define Natts_pg_description            4
#define Anum_pg_description_objoid      1
#define Anum_pg_description_classoid    2
#define Anum_pg_description_objsubid    3
#define Anum_pg_description_description 4

/* ----------------
 *      initial contents of pg_description
 * ----------------
 */

/*
 *  Because the contents of this table are taken from the other *.h files,
 *  there is no initialization here.  The initial contents are extracted
 *  by genbki.pl and loaded during initdb.
 */

#endif   /* PG_DESCRIPTION_H */