REVERSE function

The REVERSE function operates on a string and returns the characters in reverse order. For example, reverse('abcde') returns edcba. This function works on numeric and date data types as well as character data types; however, in most cases it has practical value for character strings.

Syntax

REVERSE ( expression )

Argument

expression

An expression with a character, date, timestamp, or numeric data type that represents the target of the character reversal. All expressions are implicitly converted to variable-length character strings. Trailing blanks in fixed-width character strings are ignored.

Return type

REVERSE returns a VARCHAR.

Examples

Select five distinct city names and their corresponding reversed names from the USERS table:

select distinct city as cityname, reverse(cityname)
from users order by city limit 5;

cityname | reverse
---------+----------
Aberdeen | needrebA
Abilene  | enelibA
Ada      | adA
Agat     | tagA
Agawam   | mawagA
(5 rows)

Select five sales IDs and their corresponding reversed IDs cast as character strings:

select salesid, reverse(salesid)::varchar
from sales order by salesid desc limit 5;

salesid | reverse
--------+---------
 172456 | 654271
 172455 | 554271
 172454 | 454271
 172453 | 354271
 172452 | 254271
(5 rows)