What is the method of paging in mysql

Mysql paging methods include using LIMIT clause, using ROWNUM, using subquery and LIMIT, using cursor (Cursor), using ORM framework, etc. Detailed introduction: 1. Use LIMIT clause: This is the most commonly used paging method. The number of query results can be specified through the LIMIT clause; 2. Use ROWNUM: In some old versions of MySQL, ROWNUM can be used to simulate paging; 3 , using subqueries and LIMIT, etc.

In MySQL, the common paging methods mainly include the following:

1. Use the LIMIT clause: This is the most commonly used In the paging method, the number of query results can be specified through the LIMIT clause. For example, SELECT * FROM table LIMIT 10 will return the first 10 records. If you want to paginate, you can specify an offset, such as SELECT * FROM table LIMIT 10, 20, which will return records from the 11th to the 30th.
2. Use ROWNUM: In some older versions of MySQL, ROWNUM can be used to simulate paging. For example, SELECT * FROM table WHERE ROWNUM <= 30 will return the first 30 records. However, it should be noted that ROWNUM is counted after the query results are returned, so the performance may be poor.
3. Use subqueries and LIMIT: More complex paging requirements can be achieved through a combination of subqueries and LIMIT. For example, SELECT * FROM (SELECT * FROM table ORDER BY id) AS sorted_table LIMIT 10, 20 will return the 11th to 30th records sorted by id.
4. Using a cursor: A cursor is a database object that can be used to traverse and process query result sets. In MySQL, you can use cursors for paging. For example, DECLARE cur CURSOR FOR SELECT * FROM table ORDER BY id; OPEN cur;FETCH ABSOLUTE 10 FROM cur; CLOSE cur; This code will return the 10th record sorted by id.
5. Use ORM framework: If you are using an ORM (Object Relational Mapping) framework, such as Hibernate, MyBatis, etc., they usually provide more advanced paging functions. These frameworks usually encapsulate paging parameters as objects or interfaces and provide corresponding query methods to make paging simpler and more efficient.

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