Syntax:
FOUND_ROWS()

*Note*:

The SQL_CALC_FOUND_ROWS query modifier and accompanying FOUND_ROWS()
function are deprecated as of MySQL 8.0.17; expect them to be removed
in a future version of MySQL. As a replacement, considering executing
your query with LIMIT, and then a second query with COUNT(*) and
without LIMIT to determine whether there are additional rows. For
example, instead of these queries:

SELECT SQL_CALC_FOUND_ROWS * FROM tbl_name WHERE id > 100 LIMIT 10;
SELECT FOUND_ROWS();

Use these queries instead:

SELECT * FROM tbl_name WHERE id > 100 LIMIT 10;
SELECT COUNT(*) FROM tbl_name WHERE id > 100;

COUNT(*) is subject to certain optimizations. SQL_CALC_FOUND_ROWS
causes some optimizations to be disabled.

A SELECT statement may include a LIMIT clause to restrict the number of
rows the server returns to the client. In some cases, it is desirable
to know how many rows the statement would have returned without the
LIMIT, but without running the statement again. To obtain this row
count, include an SQL_CALC_FOUND_ROWS option in the SELECT statement,
and then invoke FOUND_ROWS() afterward:

URL: https://dev.mysql.com/doc/refman/8.0/en/information-functions.html

