Strings

Strings are either literal strings, or expressions with CHAR or VARCHAR data types.

A literal string is any sequence of characters enclosed in apostrophes ('single quotes'). A SQL variable of character data type can hold a string. This is a simple example of a literal string:

An expression with a CHAR data type might be a built-in or user-defined function, or one of the many other kinds of expressions available.

'This is a string.'

Special Characters in Strings

Represent special characters in strings by escape sequences, as follows:

  • To represent an apostrophe inside a string, use two apostrophes in a row. For example:

    'John''s database'
  • To represent a newline character, use a backslash followed by n (\n). For example:

    'First line:\nSecond line:'
  • To represent a backslash character, use two backslashes in a row (\\). For example:

    'c:\\temp'
  • Hexadecimal escape sequences can be used for any character, printable or not. A hexadecimal escape sequence is a backslash followed by an x followed by two hexadecimal digits (for example, \x6d represents the letter m). For example:

    '\x00\x01\x02\x03'

Compatibility

For compatibility with Adaptive ServerĀ® Enterprise, you can set the QUOTED_IDENTIFIER database option to OFF. With this setting, you can also use double quotes to mark the beginning and end of strings. The option is ON by default.

Related concepts
SQL Operators
Subqueries in Search Conditions
Related reference
Comparison Conditions
Expressions
NULL Value
Search Conditions
Three-Valued Logic