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    In SQL, both LEFT JOIN and OUTER JOIN are used to retrieve data from multiple tables, including rows from one table that may not have matching rows in the other table(s). The choice between them depends on your specific requirements and the database you are using, as the syntax may vary slightly between different database systems.

    However, in most relational database systems, including common ones like MySQL, PostgreSQL, SQL Server, and SQLite, there is no distinction between LEFT JOIN and OUTER JOIN; they are synonymous. Both LEFT JOIN and OUTER JOIN return all rows from the left table (the table specified before the LEFT JOIN keyword) and the matching rows from the right table (the table specified after the LEFT JOIN keyword), filling in missing values with NULL when there are no matches.