In the context of MySQL, the LIMIT clause is used to constrain the number of rows returned by a query. It is particularly useful when dealing with large datasets, as it allows you to retrieve only a specified number of rows from the result set.
Syntax
The basic syntax of the LIMIT clause is as follows:
SELECT column1, column2, ... FROM table LIMIT number_of_rows;
Here, number_of_rows specifies the maximum number of rows to be returned by the query. It is a positive integer value.
Example
For example, suppose you have a table called employees and you want to retrieve the first 10 rows:
SELECT * FROM employees LIMIT 10;
This query will return only the first 10 rows from the employees table.
Additionally, the LIMIT clause can take two arguments: the offset and the number of rows to return. The offset indicates the number of rows to skip before starting to return rows. The syntax for this is:
SELECT column1, column2, ... FROM table LIMIT offset, number_of_rows;
For instance, if you want to retrieve rows 11 to 20 from the employees table:
SELECT * FROM employees LIMIT 10, 10;
This query skips the first 10 rows and returns the next 10 rows.
It’s important to note that the order of rows is crucial when using LIMIT without an ORDER BY clause. If the order is not specified, the result set’s order is undefined, and the database may return different results on subsequent executions.
In summary, the LIMIT clause in MySQL is a powerful tool for controlling the size of result sets, making it more efficient to work with large datasets and providing flexibility in retrieving specific subsets of data.