ASCII function - Amazon Redshift
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ASCII function

The ASCII function returns the ASCII code, or the Unicode code-point, of the first character in the string that you specify. The function returns 0 if the string is empty. It returns NULL if the string is null.

Syntax

ASCII('string')

Argument

string

A CHAR string or a VARCHAR string.

Return type

INTEGER

Examples

To return NULL, use the following example. The NULLIF function returns NULL if the two arguments are the same, so the input argument for the ASCII function is NULL. For more information, see NULLIF function.

SELECT ASCII(NULLIF('','')); +-------+ | ascii | +-------+ | NULL | +-------+

To return the ASCII code 0, use the following example.

SELECT ASCII(''); +-------+ | ascii | +-------+ | 0 | +-------+

To return the ASCII code 97 for the first letter of the word amazon, use the following example.

SELECT ASCII('amazon'); +-------+ | ascii | +-------+ | 97 | +-------+

To return the ASCII code 65 for the first letter of the word Amazon, use the following example.

SELECT ASCII('Amazon'); +-------+ | ascii | +-------+ | 65 | +-------+