Compiler in SQL Server [duplicate]

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What is the meaning of Stored procedures are “pre compile开发者_Python百科”?

I read that stored procedures in SQL Server are compiled before they are executed. AFAIK, a compiler is used to translating high-level language into machine language or some kind of intermediate language (such as .NET IL code). So I am wondering what does SQL Server compiler do? What is a stored procedure compiled into?

Thanks.

Compiling a query is the process of creating an Execution Plan. Compiled execution plans are cached and re-used every time a query executes.