How to parameterize the schema name in APEX

Question

Hi,
How to parameterize the schema name in APEX , in order to access different tables from the respective schema.
For example:-
select NAME display_value, CODE return_value
from paramSchema.DESC_LIST WHERE SELECTION_FLG = 'Y'
order by 1
in the above code, paramSchema will be replaced with the actual schema name duing runtime. I tried doing so by some hidden fields on page, but it didn't worked out.
I took the schema name from the respective server as per the IPof the server.
stored in a hidden field named as schema.
And replaced the same in place of schema name. But no luck.
select NAME display_value, CODE return_value
from :schema.DESC_LIST WHERE SELECTION_FLG = 'Y'
order by 1
Please help me in shorting it out.
Thanks,
Anuradha

Answer 1

Hi
In order to do that, you would need to use dynamic SQL by changing the report type to PL/SQL Function Body Returning SQL Query and have code along the lines of
DECLARE
l_sql VARCHAR2(32767);
BEGIN
l_sql := 'select NAME display_value, CODE return_value
from '||:schema||'.DESC_LIST WHERE SELECTION_FLG = 'Y'
order by 1';
RETURN l_sql;
END;However, by doing this, you lose alot of flexibility. The other options would be...
To have seperate report regions that are conditional on the value of the variable.
To use a WITH clause at the tope of the query like...
WITH src_data AS
(SELECT * FROM schema1.my_table
WHERE :schema = 'schema1'
UNION ALL
SELECT * FROM schema2.my_table
WHERE :schema = 'schema2')
SELECT *
FROM src_dataOther than that you could look at using synonyms and doing something similar.
Hope this helps.
Cheers
Ben