How Do SQLite's LIMIT and OFFSET Clauses Differ, and Which Syntax Should I Use?

Understanding SQLite's LIMIT and OFFSET in Queries

SQLite, a popular relational database, offers two ways to restrict the number of rows returned by a query: LIMIT and OFFSET. While functionally similar, their syntax differs, potentially causing confusion.

Syntax Variations

The first syntax, LIMIT <skip>, <count>, specifies the number of rows to return (count) starting at a given offset (skip) from the beginning of the result set.

The second, LIMIT <count> OFFSET <skip>, achieves the same outcome but presents the parameters in a different order. It returns count rows, beginning at the skip-th row.

Compatibility and Best Practices

SQLite supports both syntaxes, a legacy of its compatibility with other database systems like MySQL and PostgreSQL. MySQL accepts both, while PostgreSQL only supports the LIMIT <count> OFFSET <skip> form.

To avoid ambiguity, SQLite recommends the second syntax (LIMIT <count> OFFSET <skip>). Crucially, this syntax must be used with ORDER BY to guarantee consistent row selection. Without ORDER BY, the order of returned rows is unpredictable.

Illustrative Examples

Let's examine these queries against an "Animals" table:

SELECT * FROM Animals LIMIT 100 OFFSET 50

This retrieves 100 rows, starting from the 51st row (remember, OFFSET starts at 0).

SELECT * FROM Animals LIMIT 100, 50

This query, despite the different syntax, produces the same result: 100 rows starting from row 51.

Key Takeaway

SQLite's LIMIT and OFFSET clauses, though powerful tools for result set control, can be confusing due to the dual syntax. For clarity and predictable results, consistently employ LIMIT <count> OFFSET <skip> in conjunction with ORDER BY.

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