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Oracle PL/SQL Language Pocket Reference- P14: This pocket guide features quick-reference information to help you use Oracle's PL/SQL language. It includes coverage of PL/SQL features in the newest version of Oracle, Oracle8i. It is a companion to Steven Feuerstein and Bill Pribyl's bestselling Oracle PL/SQL Programming. Updated for Oracle8, that large volume (nearly 1,000 pages) fills a huge gap in the Oracle market, providing developers with a single, comprehensive guide to building applications with PL/SQL and building them the right way. . | Chapter 11 Previous III. Built-In Functions Next 11.2 Character Function Examples 11. Character Functions Contents Character Function Descriptions Character Function Examples A character function is a function that takes one or more character values as parameters and returns either a character value or a number value. The Oracle Server and PL SQL provide a number of different character datatypes including CHAR VARCHAR VARCHAR2 LONG RAW and LONG RAW. In PL SQL the three different datatype families for character data are VARCHAR2 A variable-length character datatype whose data is converted by the RDBMS CHAR The fixed-length datatype RAW A variable-length datatype whose data is not converted by the RDBMS but instead is left in raw form When a character function returns a character value that value is always of type VARCHAR2 variable length with the following two exceptions UPPER and LOWER. These functions convert to upper- and lowercase respectively and return CHAR values fixed length if the strings they are called on to convert are fixed-length CHAR arguments. PL SQL provides a rich set of character functions that allow you to get information about strings and modify the contents of those strings in very high-level powerful ways. Table 11.1 shows the character functions covered in detail in this chapter. The remaining functions not covered in this chapter are specific to National Language Support and Trusted Oracle. Table 11.1 The Built-In Character Functions Please purchase PDF Split-Merge on www.verypdf.com to remove this watermark. Name Description ASCII Returns the ASCII code of a character. CHR Returns the character associated with the specified collating code. CONCAT Concatenates two strings into one. INITCAP Sets the first letter of each word to uppercase. All other letters are set to lowercase. INSTR Returns the location in a string of the specified substring. LENGTH Returns the length of a string. LOWER Converts all letters to lowercase. LPAD Pads a string .