SQL files can contain Jinja, a lightweight templating language. Using Jinja in SQL provides a way to use control structures in your queries. For example, if statements and for loops. It also enables repeated SQL to be shared through macros.SQL files can contain Jinja, a lightweight templating language. Using Jinja in SQL provides a way to use control structures in your queries. For example, if statements and for loops. It also enables repeated SQL to be shared through macros.