[ http://issues.apache.org/jira/browse/DERBY-495?page=comments#action_12445317 ] Christian d'Heureuse commented on DERBY-495: --------------------------------------------
COALESCE is an important function and should be documented. In ISO/IEC 9075, the syntax for COALESCE is COALESCE ( expression [,expression].... ) but Derby currently does not allow COALESCE with a single argument. As long as this is not fixed, the syntax documentation should be COALESCE ( expression, expression [,expression].... ) In ISO 9075-2, COALESCE is defined as: COALESCE (V1, V2) is equivalent to the following <case specification>: CASE WHEN V1 IS NOT NULL THEN V1 ELSE V2 END COALESCE (V1, V2, ..., Vn), for n ≥ 3, is equivalent to the following <case specification>: CASE WHEN V1 IS NOT NULL THEN V1 ELSE COALESCE (V2, ..., Vn) END This could be used for the documentation. I wouldn't document that "VALUE is another name for the COALESCE function" in Derby, because thats an "inheritance" from DB2 and not part of the SQL standard. > COALESCE > -------- > > Key: DERBY-495 > URL: http://issues.apache.org/jira/browse/DERBY-495 > Project: Derby > Issue Type: Bug > Components: Documentation > Affects Versions: 10.0.2.0 > Environment: n/a > Reporter: Paul Jenkins > Priority: Minor > > The COALESCE function has been implemeted since 10.0.2.0 (at least) but isn't > documented. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira