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String concatenation is slow... Faster method for Bulk SQL string? Messages   Related Types This message was discovered on microsoft.public.dotnet.languages.vb. Responses highlighted in red are from those people who are likely to be able to contribute good, authoratitive information to this discussion. They include Microsoft employees, MVP's and others who IMHO contribute well to these kinds of discussions. Post a new message to this list... Lucas Tam Hi all, I'm concatenating a large SQL string for updating a table. There are > 80,000 commands (rows) in the SQL string. VB.NET seems to be *VERY* slow at string concatenation when the string gets large... Is it possible to execute a SQL command from a text file? .NET can streamwrite extremely fast so I was thinking of writing all the commands to a text file then executing the text file. Is this possible? Or do I have to read the File back into a string and submit it to ADO.NET? Thanks. -- Lucas Tam (Click here to reveal e-mail address) Please delete "REMOVE" from the e-mail address when replying. http://members.ebay.com/aboutme/coolspot18/ Reply to this message...        Cor Ligthert Hi Lucas, Try to avoid the concatination of strings in anyway even with stringbuilder, beside that it is not the right way, it is as well not good for security. Try to use the command.parameters for that. http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdatasqlclientsqlparameterclasstopic.asp Browse from here how to make the SQL string for that. I hope this helps? Cor Reply to this message...        Lucas Tam Lucas Tam <Click here to reveal e-mail address> wrote in news:Xns955FEE9CDD16Cnntprogerscom@140.99.99.130: [Original message clipped] Just gave StringBuilder a try... and it's MUCH faster. I read somewhere that you shouldn't reuse the Stringbuilder object since Strings are immutable. What is the best way to destory the string object for reuse in a loop? Thanks. -- Lucas Tam (Click here to reveal e-mail address) Please delete "REMOVE" from the e-mail address when replying. http://members.ebay.com/aboutme/coolspot18/ Reply to this message...        Imran Koradia (VIP) Per documentation, String Objects are immutable while StringBuilder Objects are mutable. So as long as you keep appending the sql statements to the stringbuilder object, you should be fine - you shouldn't need to destroy any objects then. At the very end when you're done building the entire sql, you can just do ToString and execute it. hope that helps.. Imran. "Lucas Tam" <Click here to reveal e-mail address> wrote in message news:Xns955FEFEB2965Dnntprogerscom@140.99.99.130... [Original message clipped] Reply to this message...        Herfried K. Wagner [MVP] (VIP) * Lucas Tam <Click here to reveal e-mail address> scripsit: [Original message clipped] What do you mean by reusing the stringbuilder? Sure, you can reuse an instance of stringbuilder as it's not immutable. -- M S Herfried K. Wagner M V P <URL:http://dotnet.mvps.org/> V B <URL:http://dotnet.mvps.org/dotnet/faqs/> Reply to this message...     System.Text.StringBuilder Ad MBR BootFX Best-of-breed application framework for .NET projects, developed by Matthew Baxter-Reynolds and MBR IT

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