-- Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved. -- -- This program is free software; you can redistribute it and/or modify -- it under the terms of the GNU General Public License as published by -- the Free Software Foundation; version 2 of the License. -- -- This program is distributed in the hope that it will be useful, -- but WITHOUT ANY WARRANTY; without even the implied warranty of -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the -- GNU General Public License for more details. -- -- You should have received a copy of the GNU General Public License -- along with this program; if not, write to the Free Software -- Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA -- -- View: statements_with_full_table_scans -- -- Lists all normalized statements that use have done a full table scan -- ordered by number the percentage of times a full scan was done, -- then by the statement latency. -- -- This view ignores SHOW statements, as these always cause a full table scan, -- and there is nothing that can be done about this. -- -- mysql> select * from statements_with_full_table_scans limit 1\G -- *************************** 1. row *************************** -- query: SELECT * FROM `schema_tables_w ... ex_usage` . `COUNT_READ` DESC -- db: sys -- exec_count: 1 -- total_latency: 88.20 ms -- no_index_used_count: 1 -- no_good_index_used_count: 0 -- no_index_used_pct: 100 -- rows_sent: 0 -- rows_examined: 1501 -- rows_sent_avg: 0 -- rows_examined_avg: 1501 -- first_seen: 2014-03-07 13:58:20 -- last_seen: 2014-03-07 13:58:20 -- digest: 64baecd5c1e1e1651a6b92e55442a288 -- CREATE OR REPLACE ALGORITHM = MERGE DEFINER = 'root'@'localhost' SQL SECURITY INVOKER VIEW statements_with_full_table_scans ( query, db, exec_count, total_latency, no_index_used_count, no_good_index_used_count, no_index_used_pct, rows_sent, rows_examined, rows_sent_avg, rows_examined_avg, first_seen, last_seen, digest ) AS SELECT sys.format_statement(DIGEST_TEXT) AS query, SCHEMA_NAME as db, COUNT_STAR AS exec_count, sys.format_time(SUM_TIMER_WAIT) AS total_latency, SUM_NO_INDEX_USED AS no_index_used_count, SUM_NO_GOOD_INDEX_USED AS no_good_index_used_count, ROUND(IFNULL(SUM_NO_INDEX_USED / NULLIF(COUNT_STAR, 0), 0) * 100) AS no_index_used_pct, SUM_ROWS_SENT AS rows_sent, SUM_ROWS_EXAMINED AS rows_examined, ROUND(SUM_ROWS_SENT/COUNT_STAR) AS rows_sent_avg, ROUND(SUM_ROWS_EXAMINED/COUNT_STAR) AS rows_examined_avg, FIRST_SEEN as first_seen, LAST_SEEN as last_seen, DIGEST AS digest FROM performance_schema.events_statements_summary_by_digest WHERE (SUM_NO_INDEX_USED > 0 OR SUM_NO_GOOD_INDEX_USED > 0) AND DIGEST_TEXT NOT LIKE 'SHOW%' ORDER BY no_index_used_pct DESC, total_latency DESC;