====== DECODE Function - PL/HQL Reference ======

DECODE function allows you to implement IF-THEN-ELSE logic.

**Syntax:**

<code language=sql>
DECODE(expr, when_exp1, then_expr1 [, ...n] [, else_expr]) 
</code>

**Notes**:

  * If //expr// is NULL it will match the first //when_exprN// that is NULL
  * If //when_exprN// is not matched //then_exprN// is not evaluated

**Examples**:

<code language=sql>
DECLARE var1 INT DEFAULT 3;

PRINT DECODE (var1, 1, 'A', 2, 'B', 3, 'C');       -- Result: C
PRINT DECODE (var1, 1, 'A', 2, 'B', 'C');          -- Result: C

SET var1 = NULL;
PRINT DECODE (var1, 1, 'A', 2, 'B', NULL, 'C');    -- Result: C  
</code>

**Compatibility:** Oracle, IBM DB2 and Teradata

**Version**: PL/HQL 0.3.1

See also:
  * [[case|CASE Expression]]