InstantForum.NET v2.9.0SQLServerCentralhttp://www.sqlservercentral.com/Forums/notifications@sqlservercentral.comMon, 17 Jun 2013 23:26:59 GMT20http://www.sqlservercentral.com/Forums/Topic1382528-65-1.aspxI need to copy more than a 100 large tables on a daily basis from Informix to SQL Server.It seems like that on the Informix side most fields are nchar. With a few exceptions these are implicitly casted as varchar on the SQL Server side (that's how the data is stored). We use linked server/openquery.The copying takes forever even though we managed to improve the performance by a factor 20 or so.Now what I was considering was to Cast the nchar columns to varchar in the openquery statement, so make Informix doing the explicit conversion and [b]resulting in a higher effective throughput[/b] (based on the thought varchar consumes less space than nchar). The linked in Server is making use of a ODBC connection.I thought the syntax has to be something like:...SELECT * FROM OPENQUERY(xxx, 'Select ...CAST([invoice_no] AS VARCHAR(50)) invoice_no... from xxx.invoice')where invoice_no is nchar(50)Problem is that I cannot access the system at the moment so I cannot test this out myself.Does it make any sense what I'm doing? Would this actually result in a better performance?Is the syntax correct?HenkThu, 08 Nov 2012 08:24:44 GMTHenk de W