Oracle PL/SQL Language Pocket Reference, 4th Edition

Built-in Functions and Packages

Oracle Corporation supplies many built-in functions and packages. The following sections describe those used most often by PL/SQL developers.

Built-in Functions

The Oracle database provides dozens of built-in functions. Although most of these functions are available to both SQL and PLSQL, there are some notable exceptions. The DECODE function, for example, is not available to PL/SQL except within SQL statements included in your PL/SQL programs. The Oracle Database SQL Reference contains implementation details for the many functions defined to PL/SQL with the package STANDARD. You can view this package specification within the file stdspec.sql located in the ORACLE_HOME/rdbms/admin directory on the database server.

Conversion functions

Built-in function	Description
ASCIISTR(string)	Converts string in any character set to the ASCII version of string in the database character set.
CAST(expression AS datatype)	Converts expression to type datatype. (Use as a powerful substitute for TO_DATE.)
CHARTOROWID(string)	Converts string to a ROWID datatype.
CONVERT(string, destination_character_set, source_character_set)	Converts string from the source character set to the destination character set. (The default source character set is the database character set.)
FROM_TZ(timestamp_value, time_zone)	Adds time zone information to a TIMESTAMP value (converting it to a TIMESTAMP WITH TIME ZONE value).
HEXTORAW(string)	Converts string containing hexadecimal characters to its raw equivalent. ...