Page display of Mysql Data list

 

When the website was just released, there were not many articles, and the homepage basically listed all the content. Recently there were many articles, so you need to display them by page.

The website uses the MySQL database. The code for getting a page of articles is basically as follows:

 

Int start = countPerPage * (page-1 );

Execute select * from... limit start, countPerPage

 

You need to list some page numbers when paging, which requires the total number of articles. Generally, you can obtain data by using select count. The problem here is that in order to implement paging, the database needs to be queried twice, which is not efficient. Therefore, if you want to solve this problem with one query, you can search the database online and find the answer:

Mysql> SELECT SQL _CALC_FOUND_ROWS * FROM... WHERE... LIMIT 10;

Mysql> SELECT FOUND_ROWS ();

 

The SQL _CALC_FOUND_ROWS parameter indicates the number of query results in the query.

The FOUNT_ROWS function returns the number of results returned by the last query (SQL _CALC_FOUND_ROWS ).

 

Although select is also required twice, 2nd select statements do not need to query records and directly return results, which can be doubled.