pg_cast.h

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/*-------------------------------------------------------------------------
 *
 * pg_cast.h
 *    definition of the system "type casts" relation (pg_cast)
 *    along with the relation's initial contents.
 *
 * As of Postgres 8.0, pg_cast describes not only type coercion functions
 * but also length coercion functions.
 *
 *
 * Copyright (c) 2002-2013, PostgreSQL Global Development Group
 *
 * src/include/catalog/pg_cast.h
 *
 * NOTES
 *    the genbki.pl script reads this file and generates .bki
 *    information from the DATA() statements.
 *
 *-------------------------------------------------------------------------
 */
#ifndef PG_CAST_H
#define PG_CAST_H

#include "catalog/genbki.h"

/* ----------------
 *      pg_cast definition.  cpp turns this into
 *      typedef struct FormData_pg_cast
 * ----------------
 */
#define CastRelationId  2605

CATALOG(pg_cast,2605)
{
    Oid         castsource;     /* source datatype for cast */
    Oid         casttarget;     /* destination datatype for cast */
    Oid         castfunc;       /* cast function; 0 = binary coercible */
    char        castcontext;    /* contexts in which cast can be used */
    char        castmethod;     /* cast method */
} FormData_pg_cast;

typedef FormData_pg_cast *Form_pg_cast;

/*
 * The allowable values for pg_cast.castcontext are specified by this enum.
 * Since castcontext is stored as a "char", we use ASCII codes for human
 * convenience in reading the table.  Note that internally to the backend,
 * these values are converted to the CoercionContext enum (see primnodes.h),
 * which is defined to sort in a convenient order; the ASCII codes don't
 * have to sort in any special order.
 */

typedef enum CoercionCodes
{
    COERCION_CODE_IMPLICIT = 'i',       /* coercion in context of expression */
    COERCION_CODE_ASSIGNMENT = 'a',     /* coercion in context of assignment */
    COERCION_CODE_EXPLICIT = 'e'    /* explicit cast operation */
} CoercionCodes;

/*
 * The allowable values for pg_cast.castmethod are specified by this enum.
 * Since castcontext is stored as a "char", we use ASCII codes for human
 * convenience in reading the table.
 */
typedef enum CoercionMethod
{
    COERCION_METHOD_FUNCTION = 'f',     /* use a function */
    COERCION_METHOD_BINARY = 'b',       /* types are binary-compatible */
    COERCION_METHOD_INOUT = 'i' /* use input/output functions */
} CoercionMethod;


/* ----------------
 *      compiler constants for pg_cast
 * ----------------
 */
#define Natts_pg_cast               5
#define Anum_pg_cast_castsource     1
#define Anum_pg_cast_casttarget     2
#define Anum_pg_cast_castfunc       3
#define Anum_pg_cast_castcontext    4
#define Anum_pg_cast_castmethod     5

/* ----------------
 *      initial contents of pg_cast
 *
 * Note: this table has OIDs, but we don't bother to assign them manually,
 * since nothing needs to know the specific OID of any built-in cast.
 * ----------------
 */

/*
 * Numeric category: implicit casts are allowed in the direction
 * int2->int4->int8->numeric->float4->float8, while casts in the
 * reverse direction are assignment-only.
 */
DATA(insert (   20   21  714 a f ));
DATA(insert (   20   23  480 a f ));
DATA(insert (   20  700  652 i f ));
DATA(insert (   20  701  482 i f ));
DATA(insert (   20 1700 1781 i f ));
DATA(insert (   21   20  754 i f ));
DATA(insert (   21   23  313 i f ));
DATA(insert (   21  700  236 i f ));
DATA(insert (   21  701  235 i f ));
DATA(insert (   21 1700 1782 i f ));
DATA(insert (   23   20  481 i f ));
DATA(insert (   23   21  314 a f ));
DATA(insert (   23  700  318 i f ));
DATA(insert (   23  701  316 i f ));
DATA(insert (   23 1700 1740 i f ));
DATA(insert (  700   20  653 a f ));
DATA(insert (  700   21  238 a f ));
DATA(insert (  700   23  319 a f ));
DATA(insert (  700  701  311 i f ));
DATA(insert (  700 1700 1742 a f ));
DATA(insert (  701   20  483 a f ));
DATA(insert (  701   21  237 a f ));
DATA(insert (  701   23  317 a f ));
DATA(insert (  701  700  312 a f ));
DATA(insert (  701 1700 1743 a f ));
DATA(insert ( 1700   20 1779 a f ));
DATA(insert ( 1700   21 1783 a f ));
DATA(insert ( 1700   23 1744 a f ));
DATA(insert ( 1700  700 1745 i f ));
DATA(insert ( 1700  701 1746 i f ));
DATA(insert (  790 1700 3823 a f ));
DATA(insert ( 1700  790 3824 a f ));
DATA(insert ( 23    790 3811 a f ));
DATA(insert ( 20    790 3812 a f ));

/* Allow explicit coercions between int4 and bool */
DATA(insert (   23  16  2557 e f ));
DATA(insert (   16  23  2558 e f ));

/*
 * OID category: allow implicit conversion from any integral type (including
 * int8, to support OID literals > 2G) to OID, as well as assignment coercion
 * from OID to int4 or int8.  Similarly for each OID-alias type.  Also allow
 * implicit coercions between OID and each OID-alias type, as well as
 * regproc<->regprocedure and regoper<->regoperator.  (Other coercions
 * between alias types must pass through OID.)  Lastly, there are implicit
 * casts from text and varchar to regclass, which exist mainly to support
 * legacy forms of nextval() and related functions.
 */
DATA(insert (   20   26 1287 i f ));
DATA(insert (   21   26  313 i f ));
DATA(insert (   23   26    0 i b ));
DATA(insert (   26   20 1288 a f ));
DATA(insert (   26   23    0 a b ));
DATA(insert (   26   24    0 i b ));
DATA(insert (   24   26    0 i b ));
DATA(insert (   20   24 1287 i f ));
DATA(insert (   21   24  313 i f ));
DATA(insert (   23   24    0 i b ));
DATA(insert (   24   20 1288 a f ));
DATA(insert (   24   23    0 a b ));
DATA(insert (   24 2202    0 i b ));
DATA(insert ( 2202   24    0 i b ));
DATA(insert (   26 2202    0 i b ));
DATA(insert ( 2202   26    0 i b ));
DATA(insert (   20 2202 1287 i f ));
DATA(insert (   21 2202  313 i f ));
DATA(insert (   23 2202    0 i b ));
DATA(insert ( 2202   20 1288 a f ));
DATA(insert ( 2202   23    0 a b ));
DATA(insert (   26 2203    0 i b ));
DATA(insert ( 2203   26    0 i b ));
DATA(insert (   20 2203 1287 i f ));
DATA(insert (   21 2203  313 i f ));
DATA(insert (   23 2203    0 i b ));
DATA(insert ( 2203   20 1288 a f ));
DATA(insert ( 2203   23    0 a b ));
DATA(insert ( 2203 2204    0 i b ));
DATA(insert ( 2204 2203    0 i b ));
DATA(insert (   26 2204    0 i b ));
DATA(insert ( 2204   26    0 i b ));
DATA(insert (   20 2204 1287 i f ));
DATA(insert (   21 2204  313 i f ));
DATA(insert (   23 2204    0 i b ));
DATA(insert ( 2204   20 1288 a f ));
DATA(insert ( 2204   23    0 a b ));
DATA(insert (   26 2205    0 i b ));
DATA(insert ( 2205   26    0 i b ));
DATA(insert (   20 2205 1287 i f ));
DATA(insert (   21 2205  313 i f ));
DATA(insert (   23 2205    0 i b ));
DATA(insert ( 2205   20 1288 a f ));
DATA(insert ( 2205   23    0 a b ));
DATA(insert (   26 2206    0 i b ));
DATA(insert ( 2206   26    0 i b ));
DATA(insert (   20 2206 1287 i f ));
DATA(insert (   21 2206  313 i f ));
DATA(insert (   23 2206    0 i b ));
DATA(insert ( 2206   20 1288 a f ));
DATA(insert ( 2206   23    0 a b ));
DATA(insert (   26 3734    0 i b ));
DATA(insert ( 3734   26    0 i b ));
DATA(insert (   20 3734 1287 i f ));
DATA(insert (   21 3734  313 i f ));
DATA(insert (   23 3734    0 i b ));
DATA(insert ( 3734   20 1288 a f ));
DATA(insert ( 3734   23    0 a b ));
DATA(insert (   26 3769    0 i b ));
DATA(insert ( 3769   26    0 i b ));
DATA(insert (   20 3769 1287 i f ));
DATA(insert (   21 3769  313 i f ));
DATA(insert (   23 3769    0 i b ));
DATA(insert ( 3769   20 1288 a f ));
DATA(insert ( 3769   23    0 a b ));
DATA(insert (   25 2205 1079 i f ));
DATA(insert ( 1043 2205 1079 i f ));

/*
 * String category
 */
DATA(insert (   25 1042    0 i b ));
DATA(insert (   25 1043    0 i b ));
DATA(insert ( 1042   25  401 i f ));
DATA(insert ( 1042 1043  401 i f ));
DATA(insert ( 1043   25    0 i b ));
DATA(insert ( 1043 1042    0 i b ));
DATA(insert (   18   25  946 i f ));
DATA(insert (   18 1042  860 a f ));
DATA(insert (   18 1043  946 a f ));
DATA(insert (   19   25  406 i f ));
DATA(insert (   19 1042  408 a f ));
DATA(insert (   19 1043 1401 a f ));
DATA(insert (   25   18  944 a f ));
DATA(insert ( 1042   18  944 a f ));
DATA(insert ( 1043   18  944 a f ));
DATA(insert (   25   19  407 i f ));
DATA(insert ( 1042   19  409 i f ));
DATA(insert ( 1043   19 1400 i f ));

/* Allow explicit coercions between int4 and "char" */
DATA(insert (   18   23   77 e f ));
DATA(insert (   23   18   78 e f ));

/* pg_node_tree can be coerced to, but not from, text */
DATA(insert (  194   25    0 i b ));

/*
 * Datetime category
 */
DATA(insert (  702 1082 1179 a f ));
DATA(insert (  702 1083 1364 a f ));
DATA(insert (  702 1114 2023 i f ));
DATA(insert (  702 1184 1173 i f ));
DATA(insert (  703 1186 1177 i f ));
DATA(insert ( 1082 1114 2024 i f ));
DATA(insert ( 1082 1184 1174 i f ));
DATA(insert ( 1083 1186 1370 i f ));
DATA(insert ( 1083 1266 2047 i f ));
DATA(insert ( 1114  702 2030 a f ));
DATA(insert ( 1114 1082 2029 a f ));
DATA(insert ( 1114 1083 1316 a f ));
DATA(insert ( 1114 1184 2028 i f ));
DATA(insert ( 1184  702 1180 a f ));
DATA(insert ( 1184 1082 1178 a f ));
DATA(insert ( 1184 1083 2019 a f ));
DATA(insert ( 1184 1114 2027 a f ));
DATA(insert ( 1184 1266 1388 a f ));
DATA(insert ( 1186  703 1194 a f ));
DATA(insert ( 1186 1083 1419 a f ));
DATA(insert ( 1266 1083 2046 a f ));
/* Cross-category casts between int4 and abstime, reltime */
DATA(insert (   23  702    0 e b ));
DATA(insert (  702   23    0 e b ));
DATA(insert (   23  703    0 e b ));
DATA(insert (  703   23    0 e b ));

/*
 * Geometric category
 */
DATA(insert (  601  600 1532 e f ));
DATA(insert (  602  600 1533 e f ));
DATA(insert (  602  604 1449 a f ));
DATA(insert (  603  600 1534 e f ));
DATA(insert (  603  601 1541 e f ));
DATA(insert (  603  604 1448 a f ));
DATA(insert (  603  718 1479 e f ));
DATA(insert (  604  600 1540 e f ));
DATA(insert (  604  602 1447 a f ));
DATA(insert (  604  603 1446 e f ));
DATA(insert (  604  718 1474 e f ));
DATA(insert (  718  600 1416 e f ));
DATA(insert (  718  603 1480 e f ));
DATA(insert (  718  604 1544 e f ));

/*
 * INET category
 */
DATA(insert (  650  869    0 i b ));
DATA(insert (  869  650 1715 a f ));

/*
 * BitString category
 */
DATA(insert ( 1560 1562    0 i b ));
DATA(insert ( 1562 1560    0 i b ));
/* Cross-category casts between bit and int4, int8 */
DATA(insert (   20 1560 2075 e f ));
DATA(insert (   23 1560 1683 e f ));
DATA(insert ( 1560   20 2076 e f ));
DATA(insert ( 1560   23 1684 e f ));

/*
 * Cross-category casts to and from TEXT
 *
 * We need entries here only for a few specialized cases where the behavior
 * of the cast function differs from the datatype's I/O functions.  Otherwise,
 * parse_coerce.c will generate CoerceViaIO operations without any prompting.
 *
 * Note that the castcontext values specified here should be no stronger than
 * parse_coerce.c's automatic casts ('a' to text, 'e' from text) else odd
 * behavior will ensue when the automatic cast is applied instead of the
 * pg_cast entry!
 */
DATA(insert (  650   25  730 a f ));
DATA(insert (  869   25  730 a f ));
DATA(insert (   16   25 2971 a f ));
DATA(insert (  142   25    0 a b ));
DATA(insert (   25  142 2896 e f ));

/*
 * Cross-category casts to and from VARCHAR
 *
 * We support all the same casts as for TEXT.
 */
DATA(insert (  650 1043  730 a f ));
DATA(insert (  869 1043  730 a f ));
DATA(insert (   16 1043 2971 a f ));
DATA(insert (  142 1043    0 a b ));
DATA(insert ( 1043  142 2896 e f ));

/*
 * Cross-category casts to and from BPCHAR
 *
 * We support all the same casts as for TEXT.
 */
DATA(insert (  650 1042  730 a f ));
DATA(insert (  869 1042  730 a f ));
DATA(insert (   16 1042 2971 a f ));
DATA(insert (  142 1042    0 a b ));
DATA(insert ( 1042  142 2896 e f ));

/*
 * Length-coercion functions
 */
DATA(insert ( 1042 1042  668 i f ));
DATA(insert ( 1043 1043  669 i f ));
DATA(insert ( 1083 1083 1968 i f ));
DATA(insert ( 1114 1114 1961 i f ));
DATA(insert ( 1184 1184 1967 i f ));
DATA(insert ( 1186 1186 1200 i f ));
DATA(insert ( 1266 1266 1969 i f ));
DATA(insert ( 1560 1560 1685 i f ));
DATA(insert ( 1562 1562 1687 i f ));
DATA(insert ( 1700 1700 1703 i f ));

#endif   /* PG_CAST_H */