In the first blog post of this introductory series for learning T-SQL, I talked about what SQL is. That then raises the obvious question, about what T-SQL is.
Well the promise of SQL was that we'd have one language, and it would work with all databases. Did that end up working? Well, sort of.
Committees, even the ANSI committees, are notoriously hard to make progress in. Everyone has no doubt heard the joke about a camel being a horse designed by a committee.
One problem is that even when you have a standard, different people will implement it in different ways. It's impossible for the standard to be 100% clear, and so they'll read and implement the standard differently. That can make two products different, even if they both claim to have implemented the ANSI standard.
But the problem in the case of SQL was that people needed to do more things than the language supported, particularly in the early days. Rather than wait for the committee to come up with a standard way of doing things, each company created their own variation of SQL.
And so Oracle has PL/SQL; Postgres has pgsql; and SQL Server (which was originally derived from Sybase code) has T-SQL.
So T-SQL is a Microsoft-specific implementation of the SQL language, and it's used for working with SQL Server, which today, looks nothing like its Sybase origins.
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