pg_depend.h

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/*-------------------------------------------------------------------------
 *
 * pg_depend.h
 *    definition of the system "dependency" relation (pg_depend)
 *    along with the relation's initial contents.
 *
 *
 * Portions Copyright (c) 1996-2013, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/catalog/pg_depend.h
 *
 * NOTES
 *    the genbki.pl script reads this file and generates .bki
 *    information from the DATA() statements.
 *
 *-------------------------------------------------------------------------
 */
#ifndef PG_DEPEND_H
#define PG_DEPEND_H

#include "catalog/genbki.h"

/* ----------------
 *      pg_depend definition.  cpp turns this into
 *      typedef struct FormData_pg_depend
 * ----------------
 */
#define DependRelationId  2608

CATALOG(pg_depend,2608) BKI_WITHOUT_OIDS
{
    /*
     * Identification of the dependent (referencing) object.
     *
     * These fields are all zeroes for a DEPENDENCY_PIN entry.
     */
    Oid         classid;        /* OID of table containing object */
    Oid         objid;          /* OID of object itself */
    int32       objsubid;       /* column number, or 0 if not used */

    /*
     * Identification of the independent (referenced) object.
     */
    Oid         refclassid;     /* OID of table containing object */
    Oid         refobjid;       /* OID of object itself */
    int32       refobjsubid;    /* column number, or 0 if not used */

    /*
     * Precise semantics of the relationship are specified by the deptype
     * field.  See DependencyType in catalog/dependency.h.
     */
    char        deptype;        /* see codes in dependency.h */
} FormData_pg_depend;

/* ----------------
 *      Form_pg_depend corresponds to a pointer to a row with
 *      the format of pg_depend relation.
 * ----------------
 */
typedef FormData_pg_depend *Form_pg_depend;

/* ----------------
 *      compiler constants for pg_depend
 * ----------------
 */
#define Natts_pg_depend             7
#define Anum_pg_depend_classid      1
#define Anum_pg_depend_objid        2
#define Anum_pg_depend_objsubid     3
#define Anum_pg_depend_refclassid   4
#define Anum_pg_depend_refobjid     5
#define Anum_pg_depend_refobjsubid  6
#define Anum_pg_depend_deptype      7


/*
 * pg_depend has no preloaded contents; system-defined dependencies are
 * loaded into it during a late stage of the initdb process.
 *
 * NOTE: we do not represent all possible dependency pairs in pg_depend;
 * for example, there's not much value in creating an explicit dependency
 * from an attribute to its relation.  Usually we make a dependency for
 * cases where the relationship is conditional rather than essential
 * (for example, not all triggers are dependent on constraints, but all
 * attributes are dependent on relations) or where the dependency is not
 * convenient to find from the contents of other catalogs.
 */

#endif   /* PG_DEPEND_H */