Sql_calc_found_rows features in MySQL

MySQL database does not conform to the SQL standard a lot of places, such as timestamp column processing, string comparison default case is not sensitive or anything.
Sometimes these problems can make you depressed, especially for those who turn from other databases.
But some features are pretty interesting.

Today I found a:
Sql_calc_found_rows.

SELECT  from WHERE LIMIT ...

The so-called sql_calc_found_rows is when executing a query with limit, with statistics on how many results will be output if no limit is added.

After the data is obtained, the number of results without limit can be obtained by found_rows ():

SELECT Found_rows ()

Sql_calc_found_rows features in MySQL