LEFT OUTER JOIN Information_Sales A ON Case IF EID = 0 or PID = 0 then SID = 148 ELSE UDF.NEW (EID,PID) = A.SID
Its important to remember that a CASE expression is an expression, which produces a single scalar value. It is not an IF clause.
Assuming that the SID = 148 and A.Sid are the same column. You want something more like this
LEFT OUTER JOIN Information_Sales A on A.SID = Case When EID = 0 then 148 when PID = 0 then 148 else UDF.NEW (EID,PID) end
Note: NO guarantees on performance of such a join. You may well be better off doing separate queries
LEFT OUTER JOIN Information_Sales A on SID = 148
WHERE EID = 0 or PID = 0
LEFT OUTER JOIN Information_Sales A on UDF.NEW (EID,PID)
WHERE EID <> 0 and PID <> 0
As has already been pointed out. A lot more information is needed before anyone can give you solid, specific advice.
__________________________________________________Against stupidity the gods themselves contend in vain. -- Friedrich Schiller Stop, children, what's that sound? Everybody look what's going down. -- Stephen Stills