Syntax:
SHOW ERRORS [LIMIT [offset,] row_count]
SHOW COUNT(*) ERRORS

SHOW ERRORS is a diagnostic statement that is similar to SHOW WARNINGS,
except that it displays information only for errors, rather than for
errors, warnings, and notes.

The LIMIT clause has the same syntax as for the SELECT statement. See
http://dev.mysql.com/doc/refman/5.5/en/select.html.

The SHOW COUNT(*) ERRORS statement displays the number of errors. You
can also retrieve this number from the error_count variable:

SHOW COUNT(*) ERRORS;
SELECT @@error_count;

SHOW ERRORS and error_count apply only to errors, not warnings or
notes. In other respects, they are similar to SHOW WARNINGS and
warning_count. In particular, SHOW ERRORS cannot display information
for more than max_error_count messages, and error_count can exceed the
value of max_error_count if the number of errors exceeds
max_error_count.

URL: http://dev.mysql.com/doc/refman/5.5/en/show-errors.html

