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copied!<p>first you need to know and understand that every SQL engine works with a different SQL grammar. Despite the SQL ANSI standard, no language on earth respects it 100%. Moreover, every large and known SQL engine adds own methods and stuff to the original grammar.</p> <p>So, if you want to do a conversion, the easiest way is to achieve a middle SQL layer. That means, to create an agnostic SQL grammar out of the very common features in every well known SQL engine (it would result in something like SQL ansi plus every feature present in every engine, like TOP). Once you have this, you have to make the conversion to this middle layer, and from this middle layer for each SQL variation you need.</p> <p>I told you this because I needed this exact thing at my work, and that was the only way to actually achieve it, and made it reusable. Having a tool gives you the job to actually manually convert every single query, and make huge SWITCHs just to choose the query, or to have an inherited class for every engine.</p> <p>I tell you what I've done: I created the BNF of my SQL middle grammar, then created a tree parser with GoldParser for C#. Then I created individual rules for each rule in the grammar to be converted to each SQL dialect. It's a huge and tedious job, I know. But they'd paid me to do it...</p> <p>If you don't have the time to accomplish this, you could use ODBC. Every SQL engine has an ODBC connector, and the ODBC itself will act as a middle abstract layer. But, it's not as happy as it sounds, because only simple queries will maintain this illusion... hard stuff like UNION, JOINs, and metadata creation won't be the same.</p> <p>I hope it helped,</p> <p>good luck</p>

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