InstantForum.NET v2.9.0SQLServerCentralhttp://www.sqlservercentral.com/Forums/notifications@sqlservercentral.comSun, 19 May 2013 23:34:56 GMT20http://www.sqlservercentral.com/Forums/Topic1360029-1550-1.aspxIf there is no where/order by clause in your query then indexes are unlikely to help you.Mon, 17 Sep 2012 09:52:23 GMTAnimal Magichttp://www.sqlservercentral.com/Forums/Topic1360029-1550-1.aspxWhat is the base line for that? If my table is having few millions of records (ex: 20 millions) then what is best approach. Obviously we have to create index on source tables only right? if we are not using any where clause how the index will be beneficial?Mon, 17 Sep 2012 06:21:48 GMTSQL*http://www.sqlservercentral.com/Forums/Topic1360029-1550-1.aspxIt depends on the size of your database, number of tables and rows in them.Mon, 17 Sep 2012 02:56:20 GMTSudhakar Vallamsettyhttp://www.sqlservercentral.com/Forums/Topic1360029-1550-1.aspxHi,I am importing whole data (with out any where condition) from a database, and that database tables donot have any indexes. Is there any impact on performance of the script if tables don't have indexes? As per my knowledge, if the table have clustered index it will be good. because the data pages will in an order so fetching will be good.Please correct me if i am wrong.Thank you,Mon, 17 Sep 2012 02:46:46 GMTSQL*