LPAD and RPAD functions

These functions prepend or append characters to a string, based on a specified length.

Syntax

LPAD(string1, length, [ string2 ])

RPAD(string1, length, [ string2 ])

Arguments

string1

A CHAR string, a VARCHAR string, or an expression that implicitly evaluates to a CHAR or VARCHAR type.

length

An integer that defines the length of the result of the function. The length of a string is based on the number of characters, not bytes, so that multi-byte characters are counted as single characters. If string1 is longer than the specified length, it is truncated (on the right). If length is zero or a negative number, the result of the function is an empty string.

string2

(Optional) One or more characters that are prepended or appended to string1. If this argument is not specified, spaces are used.

Return type

VARCHAR

Examples

The following examples use data from the EVENT table in the TICKIT sample database. For more information, see Sample database.

To truncate a specified set of event names to 20 characters and prepend the shorter names with spaces, use the following example.

SELECT LPAD(eventname, 20) FROM event
WHERE eventid BETWEEN 1 AND 5 ORDER BY 1;

+---------------------+
|         lpad        |
+---------------------+
|              Salome |
|        Il Trovatore |
|       Boris Godunov |
|     Gotterdammerung |
|La Cenerentola (Cind |
+-----------------------+

To truncate the same set of event names to 20 characters but append the shorter names with 0123456789, use the following example.

SELECT RPAD(eventname, 20,'0123456789') FROM event
WHERE eventid BETWEEN 1 AND 5 ORDER BY 1;

+----------------------+
|         rpad         |
+----------------------+
| Boris Godunov0123456 |
| Gotterdammerung01234 |
| Il Trovatore01234567 |
| La Cenerentola (Cind |
| Salome01234567890123 |
+----------------------+