SHOW Statements | time_zone | SYSTEM | | timestamp | 1530906638.765316 | | tls_version | TLSv1,TLSv1.1,TLSv1.2 | | tmp_table_size | 16777216 | | tmpdir | /tmp | | transaction_alloc_block_size | 8192 | | transaction_allow_batching | OFF | | transaction_isolation | REPEATABLE-READ | | transaction_prealloc_size | 4096 | | transaction_read_only | OFF | | transaction_write_set_extraction | XXHASH64 | | unique_checks | ON | | updatable_views_with_limit | YES | | version | 8.0.12 | | version_comment | MySQL Community Server - GPL | | version_compile_machine | x86_64 | | version_compile_os | Linux | | version_compile_zlib | 1.2.11 | | wait_timeout | 28800 | | warning_count | 0 | | windowing_use_high_precision | ON | +--------------------------------------------+------------------------------+ With a  LIKE  clause, the statement displays only rows for those variables with names that match the pattern. To obtain the row for a specific variable, use a  LIKE  clause as shown: To get a list of variables whose name match a pattern, use the  %  wildcard character in a  LIKE  clause: Wildcard characters can be used in any position within the pattern to be matched. Strictly speaking, because  _  is a wildcard that matches any single character, you should escape it as  \_  to match it literally. In practice, this is rarely necessary. SHOW VARIABLES LIKE ’max_join_size’; SHOW SESSION VARIABLES LIKE ’max_join_size’; SHOW VARIABLES LIKE ’%size%’; SHOW GLOBAL VARIABLES LIKE ’%size%’; SHOW WARNINGS [LIMIT [ offset ,]  row_count ] SHOW COUNT(*) WARNINGS 13.7.7.42 SHOW WARNINGS Statement SHOW WARNINGS  is a diagnostic statement that displays information about the conditions (errors, warnings, and notes) resulting from executing a statement in the current session. Warnings are generated for DML statements such as  INSERT ,  UPDATE , and  LOAD DATA  as well as DDL statements such as CREATE TABLE  and  ALTER TABLE . The  LIMIT  clause has the same syntax as for the  SELECT  statement. See Section 13.2.10, “SELECT Statement” . SHOW WARNINGS  is also used following  EXPLAIN , to display the extended information generated by EXPLAIN . See Section 8.8.3, “Extended EXPLAIN Output Format” . SHOW WARNINGS  displays information about the conditions resulting from execution of the most recent nondiagnostic statement in the current session. If the most recent statement resulted in an error during parsing,  SHOW WARNINGS  shows the resulting conditions, regardless of statement type (diagnostic or nondiagnostic). The  SHOW COUNT(*) WARNINGS  diagnostic statement displays the total number of errors, warnings, and notes. You can also retrieve this number from the  warning_count  system variable: 2966