COALESCE

Returns the value of the first non-null expression in the list. If all expressions evaluate to null, then COALESCE returns null.

COALESCE conforms to the ANSI SQL-92 standard.

Behavior Type

Immutable

Syntax

COALESCE ( expression[,…] );

Example

=> SELECT product_description, COALESCE(
     lowest_competitor_price, highest_competitor_price, average_competitor_price) AS price 
     FROM product_dimension LIMIT 10;
     product_description     | price
-----------------------------+-------
 Brand #313 corn muffins     |   565
 Brand #591 hot dogs         |   323
 Brand #1247 american cheese |   263
 Brand #1510 whole milk      |   183
 Brand #2549 vegatable soup  |   491
 Brand #4520 catfish         |   113
 Brand #4684 onions          |    56
 Brand #6078 salmon          |   195
 Brand #6924 bananas         |    80
 Brand #7912 green peppers   |   180
(10 rows)

See Also