BIT BIT_LENGTH

CASCADED CATALOG COLLATION CONNECT CONNECTION

CONSTRAINTS CONTINUE CONVERT CORRESPONDING COUNT

DATE DEALLOCATE DEC DESCRIBE DESCRIPTOR DIAGNOSTICS DISCONNECT DOMAIN

DATE DEALLOCATE DEC DEFERRABLE DEFERRED DESCRIBE DESCRIPTOR

DIAGNOSTICS DISCONNECT DOMAIN

END-EXEC ESCAPE EXCEPT EXCEPTION EXEC EXTERNAL

FIRST FOUND

GET GO GOTO

IDENTITY IMMEDIATE INDICATOR INITIALLY INPUT INTERSECT ISOLATION

LASTLEVELLOWER

IDENTITY IMMEDIATE INDICATOR INITIALLY INPUT INTERSECT

LAST LOWER

MAX MIN MODULE

OCTET_LENGTH OPEN OUTPUT OVERLAPS

PREPARE PRESERVE

ABSOLUTE ACTION

DAY

HOUR

INSENSITIVE

INSENSITIVEISOLATION

KEY

LANGUAGE

LANGUAGELEVEL

MATCH MINUTE MONTH

NEXT

OF ONLY OPTION

<programlisting>

ADA

C CATALOG_NAME CHARACTER_SET_CATALOG CHARACTER_SET_NAME

CHARACTER_SET_SCHEMA CLASS_ORIGIN COBOL COLLATION_CATALOG

COLLATION_NAME COLLATION_SCHEMA COLUMN_NAME

COMMAND_FUNCTION CONDITION_NUMBER

CONNECTION_NAME CONSTRAINT_CATALOG CONSTRAINT_NAME

CONSTRAINT_SCHEMA CURSOR_NAME

CHARACTER_SET_SCHEMA CLASS_ORIGIN COBOL COLLATION_CATALOG

COLLATION_NAME COLLATION_SCHEMA COLUMN_NAME

COMMAND_FUNCTION CONDITION_NUMBER

CONNECTION_NAME CONSTRAINT_CATALOG CONSTRAINT_NAME

CONSTRAINT_SCHEMA CURSOR_NAME

DATA DATE_TIME_INTERVAL_CODE DATE_TIME_INTERVAL_PRECISION

DYNAMIC_FUNCTION

DYNAMIC_FUNCTION

FORTRAN

LENGTH

MESSAGE_LENGTH MESSAGE_OCTET_LENGTH MORE MUMPS

NAME NULLABLE NUMBER

PAD PASCAL PLI

REPEATABLE RETURNED_LENGTH RETURNED_OCTET_LENGTH

RETURNED_SQLSTATE ROW_COUNT

SCALE SCHEMA_NAME SERVER_NAME SPACE

SUBCLASS_ORIGIN

RETURNED_SQLSTATE ROW_COUNT

SCALE SCHEMA_NAME SERVER_NAME SPACE SUBCLASS_ORIGIN

TABLE_NAME

UNCOMMITTED UNNAMED

</programlisting>

<title>Constants</title>

<para>

There are six types of

<firstterm>constants</firstterm>

for use in SQL. They are described below.

There are three <firstterm>implicitly typed constants</firstterm>

for use in <productname>Postgres</productname>: strings, integers,

and floating point numbers. Constants can

also be specified with explicit types, which can enable more

accurate representation and more efficient handling by the

backend. The implicit constants are described below; explicit

constants are discussed afterwards.

</para>

<sect2>

<para>

A constant of an

<emphasis>arbitrary</emphasis>

type can be entered using the notations:

type can be entered usingany one ofthe following notations:

<synopsis>

<replaceable>type</replaceable> '<replaceable>string</replaceable>'