Let&#039s say that I have a SQL Server and 2 databases with some tables in them.<BR>DB1 : Table11, Table12<BR>DB2 : Table21<BR><BR>I have an open connection to DB1 but I need to write a SQL statement which query table Table21 from DB2<BR><BR>If I write the SQL Statement like :<BR><BR>SELECT Table11.Field1 FROM Table11, DB2.dbo.Table21 WHERE Table11.Field1 = Table21.Field2<BR><BR>the performance is very poor (response time about 90sec) in the case there are a large number of records (2000-3000 items) to be retrieved.<BR>If I change a little bit the SQL statement not to query Table21 from BD2 the response time becomes under 1 sec for the same number of items retrieved but this doesn&#039t make me happy because that result is not what I want.<BR>I tried to retrieve the records from Table11 and after that to check the values against Table21 but the performance was even worse.<BR>What can I do to improve performance for a SQL statement which query tables from different databases ?<BR><BR>Thanks<BR><BR><BR>