Limit the number of rows in SQL

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In SQL, there may be a need to limit the number of rows returned by a SQL query.

Limit Clause

Users can limit the number of rows that a SELECT statement will return by using the SQL command LIMIT. Many relational database management systems, including MySQL, PostgreSQL, SQLite, and Oracle, support the clause.

The syntax for the LIMIT clause is as follows:

SELECT column1, column2, ... FROM table_name LIMIT [number of rows];

Table_name, which appears in the syntax above, refers to the name of the table that holds the requested data. The columns that should be included in the result set are column 1, column 2,... Finally, the maximum number of rows that the query may return is specified by the number of rows option.

For example, to limit the number of rows returned from a table named "orders" to 10, use the following SQL statement:

SELECT * FROM orders LIMIT 10;

This statement will return the first 10 rows of the "orders" table.

TOP Clause

Microsoft SQL Server and Sybase also offer the TOP clause, a similar SQL statement. This sentence is used to restrict the number of rows that a SELECT statement returns.

The syntax for the TOP clause is as follows:

SELECT TOP [number of rows] column1, column2, ... FROM table_name;

Table_name, which appears in the syntax above, refers to the name of the table that holds the requested data. The columns that should be included in the result set are column 1, column 2,... Finally, the maximum number of rows that the query may return is specified by the number of rows option. Using the TOP clause, you could, for instance, set a limit of 10 for the number of rows returned from the "orders" table.

Use the following SQL statement:

SELECT TOP 10 * FROM orders;

This statement will return the first 10 rows of the "orders" table.

ROWNUM Keyword

The ROWNUM keyword is one of the features that Oracle SQL supports. This term is used to restrict how many rows a SELECT statement returns.

The syntax for the ROWNUM keyword is as follows:

SELECT column1, column2, ... FROM table_name WHERE ROWNUM <= [number of rows];

Table_name, which appears in the syntax above, refers to the name of the table that holds the requested data. The columns that should be included in the result set are column 1, column 2,... Finally, the maximum number of rows that the query may return is specified by the number of rows option.

For example, to limit the number of rows returned from a table named "orders" to 10 using the ROWNUM keyword.

Use the following SQL statement:

SELECT * FROM orders WHERE ROWNUM <= 10;

This statement will return the first 10 rows of the "orders" table.

When working with big datasets, limiting the number of rows in a SQL query might be helpful. Powerful capabilities like the LIMIT, TOP, and ROWNUM clauses allow users to quickly and easily access the data they require. Users can optimize SQL queries and enhance the functionality of programmes by using these clauses.

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