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Compilers

Compilers are the component responsible to transform a Query instance to a SQL string that can be executed directly by the database engine.

Supported compilers

Currently, SqlKata query builder supports natively the following compilers Sql Server, SQLite, MySql, PostgreSql, Oracle and Firebird.

Some noticeable difference

Theoretically the output of different compilers should be similar, this is true for the 80% of the cases, however in some edge cases the output can be very different, for instance take a look how the Limit and Offset clause get compiled in each compiler

//:playground
new Query("Posts").Limit(10).Offset(20);

Sql Server

SELECT * FROM [Posts] ORDER BY (SELECT 0) OFFSET 20 ROWS FETCH NEXT 10 ROWS ONLY

Legacy Sql Server (< 2012)

SELECT * FROM (
    SELECT *, ROW_NUMBER() OVER (ORDER BY (SELECT 0)) AS [row_num] FROM [Posts]
) WHERE [row_num] BETWEEN 21 AND 30

MySql

SELECT * FROM `Posts` LIMIT 10 OFFSET 20

PostgreSql

SELECT * FROM "Posts" LIMIT 10 OFFSET 20

In this documentation, we will display the queries compiled by the SqlServer Compiler only, except for the queries where the output is not the same.

Supporting Legacy SqlServer < 2012

Set the UseLegacyPagination flag to true if you want to target legacy Sql Server.

var compiler = new SqlServerCompiler {
    UseLegacyPagination = true
}