====== COALESCE Function - PL/HQL Reference======

COALESCE function returns first non-NULL expression.

**Syntax**:

<code language="sql">
COALESCE(expr1, expr2 [, expr3, ...]); 
</code>

**Parameters:**

| **Parameter** | **Type** | **Value** |
| exprN | Any | Variable or expression |

**Notes**:

  * When first non-NULL expression is found the following expressions are not evaluated
  * COALESCE and [[nvl|NVL]] functions are synonyms

**Return Value:**

  * First non-NULL expression
  * NULL if all expressions evaluate to NULL

**Return Type:**

The data type of first non-NULL expression.

**Example 1:**

<code language="sql">
COALESCE(NULL, 1, 2, 3); 
</code> 

Result: 1

**Compatibility**: Oracle, IBM DB2, Teradata, Microsoft SQL Server, PostgreSQL, MySQL and Netezza

**Version**: PL/HQL 0.03

See also:
  * [[nvl|NVL]]