IS_CHAR function - Amazon Redshift
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IS_CHAR function

Checks whether a value is a CHAR. The IS_CHAR function returns true for strings that have only ASCII characters, because the CHAR type can store only characters that are in the ASCII format. The function returns false for any other values.

Syntax

IS_CHAR(super_expression)

Arguments

super_expression

A SUPER expression or column.

Return type

BOOLEAN

Examples

To check if t is a CHAR using the IS_CHAR function, use the following example.

CREATE TABLE t(s SUPER); INSERT INTO t VALUES ('t'); SELECT s, IS_CHAR(s) FROM t; +-----+---------+ | s | is_char | +-----+---------+ | "t" | true | +-----+---------+