ggk.krishna

 Profile Answers by ggk.krishna 

• Apr 8th, 2007

 

Hi ,
1.  In LOOKUP SQL override if you add or subtract ports from the SELECT statement, the session fails.

2.  In LOOKUP, if you override the ORDER BY statement, the session fails if the ORDER BY statement does not contain the condition ports in the same order they appear in the Lookup condition

chandrarekha

• Sep 28th, 2007

 

You can use SQL override in lookup if you have
1. More than one look up table
2. If you use where condition to reduce the records in the cache.

Hemanth Kumar M.N

 Profile Answers by Hemanth Kumar M.N 

• Dec 15th, 2007

 

If you write a query in source qualifier(to override using sql editor) and press validate you can recognise whether the querry written is right or wrong.

But in lookup override if the querry is wrong and if you press validate button.You cannot recognise,but when you run a session you will get error message and session fails

sarada

• Nov 28th, 2013

 

using source qualifier u can extract the data from sources,in over ride u can write the queries to run in the data base,where as in sql t/f u can write and run the queries in database and get the result at any point in the mapping pipeline,similar to this lookup u can join 2 or more tables and can write the over ride(queries will run on informatica engine

Rupesh Lokhande

• Oct 4th, 2018

 

1. SQL Override is to limit the number of incoming rows entering the mapping pipeline
- Lookup Override is to limit the number of lookup rows to avoid the whole table scan by saving the lookup time & cache it uses.
2.Lookup Override uses "Order By" clause by default
- SQL Override doesnt uses it & should provide in our query if we require it.
3.SQL Override can provide any kind of join by writing the query
- Lookup Override provides only Non-Equi joins
4. Lookup Override gives only one record even if it finds multiple records for a single condition
- SQL Override doesn’t do that.