索引的执行计划变化
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Mon Jan 6 18:48:26 2020 autopilot@10.10.10.11 ((none)) > use event; Database changed Mon Jan 6 18:48:30 2020 autopilot@10.10.10.11 (event) > explain SELECT a.* FROM event as a INNER JOIN current as b on a.`event_id` = b.`event_id` AND a.`event_ts` = b.`event_ts` INNER JOIN event_receiver as c on a.`id` = c.`event_id` WHERE (c.`username` = ‘zhaolilei‘ AND a.`priority` in (‘0‘, ‘1‘, ‘2‘) AND b.`status` = ‘PROBLEM‘) GROUP BY a.`id` ORDER BY c.`event_ts` desc LIMIT 100 OFFSET 0; +----+-------------+-------+--------+-----------------------------------+--------------+---------+------------------+---------+----------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+-----------------------------------+--------------+---------+------------------+---------+----------------------------------------------+ | 1 | SIMPLE | c | ref | idx_username,idx_event_id | idx_username | 98 | const | 1721438 | Using where; Using temporary; Using filesort | | 1 | SIMPLE | a | eq_ref | PRIMARY,idx_event_id,idx_event_ts | PRIMARY | 8 | event.c.event_id | 1 | Using where | | 1 | SIMPLE | b | eq_ref | PRIMARY,idx_event_ts | PRIMARY | 194 | event.a.event_id | 1 | Using where | +----+-------------+-------+--------+-----------------------------------+--------------+---------+------------------+---------+----------------------------------------------+ 3 rows in set (0.00 sec) Mon Jan 6 18:48:32 2020 autopilot@10.10.10.11 (event) > show index from event; +-------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ | Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | +-------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ | event | 0 | PRIMARY | 1 | id | A | 29439482 | NULL | NULL | | BTREE | | | | event | 1 | idx_pdl | 1 | pdl | A | 17 | NULL | NULL | | BTREE | | | | event | 1 | idx_event_id | 1 | event_id | A | 588789 | NULL | NULL | YES | BTREE | | | | event | 1 | idx_event_ts | 1 | event_ts | A | 2943948 | NULL | NULL | YES | BTREE | | | +-------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ 4 rows in set (0.01 sec) Mon Jan 6 18:48:35 2020 autopilot@10.10.10.11 (event) > Mon Jan 6 18:38:40 2020 autopilot@10.10.10.10 (event) > explain SELECT a.* FROM event as a INNER JOIN current as b on a.`event_id` = b.`event_id` AND a.`event_ts` = b.`event_ts` INNER JOIN event_receiver as c on a.`id` = c.`event_id` WHERE (c.`username` = ‘zhaolilei‘ AND a.`priority` in (‘0‘, ‘1‘, ‘2‘) AND b.`status` = ‘PROBLEM‘) GROUP BY a.`id` ORDER BY c.`event_ts` desc LIMIT 100 OFFSET 0; +----+-------------+-------+------+-----------------------------------+--------------+---------+------------------+--------+----------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+-----------------------------------+--------------+---------+------------------+--------+----------------------------------------------+ | 1 | SIMPLE | b | ALL | PRIMARY,idx_event_ts | NULL | NULL | NULL | 175557 | Using where; Using temporary; Using filesort | | 1 | SIMPLE | a | ref | PRIMARY,idx_event_id,idx_event_ts | idx_event_ts | 99 | event.b.event_ts | 4 | Using where | | 1 | SIMPLE | c | ref | idx_username,idx_event_id | idx_event_id | 8 | event.a.id | 2 | Using where | +----+-------------+-------+------+-----------------------------------+--------------+---------+------------------+--------+----------------------------------------------+ 3 rows in set (0.00 sec) Mon Jan 6 18:39:38 2020 autopilot@10.10.10.10 (event) > show index from event; +-------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ | Table | Non_unique | Key_name | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment | +-------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ | event | 0 | PRIMARY | 1 | id | A | 30352590 | NULL | NULL | | BTREE | | | | event | 1 | idx_pdl | 1 | pdl | A | 19 | NULL | NULL | | BTREE | | | | event | 1 | idx_event_id | 1 | event_id | A | 3035259 | NULL | NULL | YES | BTREE | | | | event | 1 | idx_event_ts | 1 | event_ts | A | 7588147 | NULL | NULL | YES | BTREE | | | +-------+------------+--------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+---------------+ 4 rows in set (0.01 sec) Mon Jan 6 18:39:41 2020 autopilot@10.10.10.10 (event) > autopilot@10.10.10.10 (event) > show create table eventG; *************************** 1. row *************************** Table: event Create Table: CREATE TABLE `event` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `event_id` varchar(64) COLLATE utf8_unicode_ci DEFAULT NULL, `status` varchar(32) COLLATE utf8_unicode_ci DEFAULT NULL, `endpoint` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `hostname` varchar(64) COLLATE utf8_unicode_ci NOT NULL DEFAULT ‘‘, `is_customize` int(1) NOT NULL DEFAULT ‘1‘, `pdl` varchar(255) COLLATE utf8_unicode_ci NOT NULL DEFAULT ‘‘, `idc` varchar(16) COLLATE utf8_unicode_ci NOT NULL DEFAULT ‘‘, `current_step` int(11) DEFAULT NULL, `event_ts` varchar(32) COLLATE utf8_unicode_ci DEFAULT NULL, `metric` varchar(64) COLLATE utf8_unicode_ci DEFAULT NULL, `pushed_tags` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `left_val` double DEFAULT NULL, `func` varchar(32) COLLATE utf8_unicode_ci DEFAULT NULL, `op` varchar(4) COLLATE utf8_unicode_ci DEFAULT NULL, `right_val` double DEFAULT NULL, `max_step` int(11) DEFAULT NULL, `priority` int(11) DEFAULT NULL, `note` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `tpl_id` bigint(20) DEFAULT NULL, `action_id` bigint(20) DEFAULT NULL, `expression_id` bigint(20) DEFAULT NULL, `strategy_id` bigint(20) DEFAULT NULL, `strategy_group_id` bigint(20) DEFAULT NULL, `last_values` varchar(1024) COLLATE utf8_unicode_ci DEFAULT NULL, `db_ts` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY (`id`), KEY `idx_pdl` (`pdl`), KEY `idx_event_id` (`event_id`), KEY `idx_event_ts` (`event_ts`) USING BTREE ) ENGINE=InnoDB AUTO_INCREMENT=125698572 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci 1 row in set (0.00 sec) ERROR: No query specified
的是否v
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