How to use case when statements in ODI

Question

I need to put conditional logic before DVM look up in ODI. In the expression editor I put the following statement:-
CASE WHEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME='RCS' THEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME=EBIZ_CELL.CELL_DATA
WHEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME='FDC' THEN CONCAT(POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME,POC_JOURNAL_TEMP_SOURCE_TBL.BOOK_CODE)=EBIZ_CELL.CELL_DATA
END
It did not work,
Under Operators ->All Executions, found the error:-
905 : 42000 : java.sql.SQLException: ORA-00905: missing keyword
The description in Session Task contained:-
select     
     C1_JOURNAL_TEMPL
from     APPS.POC_JOURNAL_TEMP_SOURCE_TBL POC_JOURNAL_TEMP_SOURCE_TBL, APPS.C$_0POC_JOURNAL_TEMP_TARGET_TB
where     
     (1=1)
And (CASE
WHEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME='RCS'
THEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME=C2_CELL_DATA
WHEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME='FDC'
THEN CONCAT(POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME,POC_JOURNAL_TEMP_SOURCE_TBL.BOOK_CODE)=C2_CELL_DATA
END)
Checked the above code in PL/SQL Developer but it gave errors.
In PL/SQL developer tried to check a simple query using case-when but even that is giving errors in the case-when portion.
The query is as follows:-
select phase_code, accounting_period, sum(eff_cc) as BD_Eff_QTD
from prj_detail
where
case POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME
when 'EXT'
then
1
when 'RAC'
then
2
when 'XXX'
then
3
else
end
I would like to know what is wrong with the above code.
Please let me know what is the correct way of using case-when in PL/SQL as well as in ODI.

Answer 1

Your ODI case statement and PL/SQL Case statement both looks confusing.
You are writing case statement under where clause which is not a good practise. If you want to implement logic like-
select a,b,c from <table>
where
when cond^n^ 1 then do 1
when cond^n^ 2 then do 2
then better you seperate your query for each filter and do a union, in other words-
select a,b,c from <table>
where cond^n^ 1
union
select a,b,c from <table>
where cond^n^ 2
If you are writing case staement to retrieve a value/column (EBIZ_CELL.CELL_DATA) then no need to include it under filter.
ODI case for column EBIZ_CELL.CELL_DATA will be:
CASE
WHEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME='RCS'
THEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME
WHEN POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME='FDC'
THEN CONCAT(POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME,POC_JOURNAL_TEMP_SOURCE_TBL.BOOK_CODE)
END
Pl/SQL query-
select phase_code, accounting_period,
case POC_JOURNAL_TEMP_SOURCE_TBL.APPLICATION_NAME
when 'EXT'then 1
when 'RAC' then 2
when 'XXX' then 3
else 'default value' --- (if no else needed then can also remove else part)
end,
sum(eff_cc) as BD_Eff_QTD
from prj_detail
Suggested as per what is understood, hope it helps.
Edited by: 939451 on Jul 5, 2012 12:47 AM
Edited by: 939451 on Jul 5, 2012 12:48 AM