Re: Oracle Freakishness

On 5-2-13 15:20:23 David E. Wheeler wrote:
> This query:
> 
>     $dbh->selectrow_hashref(q{
>         SELECT c.change_id
>              , COLLECT(t.tag) AS tags
>           FROM changes   c
>           LEFT JOIN tags t ON c.change_id = t.change_id
>          WHERE c.project = ?
>          GROUP BY c.change_id
>     }, undef, 'engine');
> 
> Generates this (useless) exception:
> 
>     ORA-00932: inconsistent datatypes: expected - got - (DBD ERROR:
> error possibly near <*> indicator at char 51 in '

Perhaps this is due to

    http://docs.oracle.com/cd/E11882_01/server.112/e26088/functions031.htm#SQLRF06304 

    "COLLECT is an aggregate function that takes as its argument a
    column of any type and creates a nested table of the input type
    out of the rows selected. To get accurate results from this
    function you must use it within a CAST function."

Do you have to define a type and cast COLLECT() to that type?

-- 
Garry T. Williams