[jira] Commented: (DERBY-495) COALESCE

["Mamta A. Satoor (JIRA)" <de...@db.apache.org>]

    [ http://issues.apache.org/jira/browse/DERBY-495?page=comments#action_12318116 ] 

Mamta A. Satoor commented on DERBY-495:
---------------------------------------

I have some suggestion on what information can be included in the documentation for COALESCE/VALUE. 

First of all, the function can be added to the existing list of Built-in functions in Reference Guide. Functions like IDENTITY_VAL_LOCAL, LOCATE are explained in that section. Definition of COALESCE "This scalar function takes two or more compatible arguments and returns the first argument that is not null. The result will be null only if all the arguments are null. VALUE is another name for COALESCE function and can be used interchangeably."  The compatible datatypes and the datatype of resultant is listed in a table in the comments section of "org.apache.derby.impl.sql.compile.CoalesceFunctionNode.java" Feel free to rephrase/reword the informatio I have suggested. 
Syntax
COALESCE (expression, expression[,expression]...)

Several examples of this function can be found in org.apache.derbyTesting.tests.lang.coalesceTests.java


> COALESCE
> --------
>
>          Key: DERBY-495
>          URL: http://issues.apache.org/jira/browse/DERBY-495
>      Project: Derby
>         Type: Bug
>   Components: Documentation
>     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