5.22. PostgreSQL LIMIT clause

5.22.1. Grammar ¶

The basic syntax of a SELECT statement with a LIMIT clause is as follows:

SELECT column1, column2, columnN FROM table_name LIMIT [no of rows]

The following is the syntax when the LIMIT clause is used with the OFFSET clause:

SELECT column1, column2, columnN FROM table_name LIMIT [no of rows] OFFSET [row num]

5.22.2. Example ¶

Create the COMPANY table ( 下载 COMPANY SQL 文件 ), the data are as follows:

runoobdb# select * from COMPANY; id | name | age | address | salary ----+-------+-----+-----------+-------- 1 | Paul | 32 | California| 20000 2 | Allen | 25 | Texas | 15000 3 | Teddy | 23 | Norway | 20000 4 | Mark | 25 | Rich-Mond | 65000 5 | David | 27 | Texas | 85000 6 | Kim | 22 | South-Hall| 45000 7 | James | 24 | Houston | 10000 (7 rows)

The following example will find a limited amount of data, that is, read 4 pieces of data:

runoobdb=# SELECT * FROM COMPANY LIMIT 4;

The following results are obtained:

 id | name | age | address | salary ----+-------+-----+-------------+-------- 1 | Paul | 32 | California | 20000 2 | Allen | 25 | Texas | 15000 3 | Teddy | 23 | Norway | 20000 4 | Mark | 25 | Rich-Mond | 65000 (4 rows)

However, in some cases, you may need to extract the record from a specific offset.

The following is an example of extracting three records from the third bit:

runoobdb=# SELECT * FROM COMPANY LIMIT 3 OFFSET 2;

The following results are obtained:

 id | name | age | address | salary ----+-------+-----+-----------+-------- 3 | Teddy | 23 | Norway | 20000 4 | Mark | 25 | Rich-Mond | 65000 5 | David | 27 | Texas | 85000 (3 rows)

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