NVL

Syntax

NVL(str1,replace_with)

Purpose

You can call this function to replace the NULL value with the specified value. If the value of str1 is NULL, the value specified by replace_with is returned. str1 is generally a column name. replace_with can be a literal (for example, a hard-coded value), a reference to another column, or an expression.

This replacement improves the output.

Examples

obclient> SELECT NVL(NULL, 0), NVL(NULL, 'a');
+--------------+----------------+
 NVL(NULL, 0)  NVL(NULL, 'a') 
+--------------+----------------+
            0  a              
+--------------+----------------+
1 row in set (0.00 sec)