mysql创建全文索引和覆盖索引以及复合索引

SELECT  *  FROM  net_collect

EXPLAIN SELECT  *  FROM  net_collect WHERE net_name LIKE '%已经%'

-- 创建全文索引
ALTER TABLE net_collect ADD FULLTEXT INDEX content_fulltext (net_name);

EXPLAIN SELECT  *  FROM  net_collect WHERE  MATCH (net_name) AGAINST ('已经');


-- 覆盖索引
CREATE INDEX covering_index ON net_collect (net_operate_time,net_name);

EXPLAIN SELECT  id,net_name  FROM  net_collect WHERE 
net_operate_time BETWEEN '2023-01-01 00:00:00' AND '2023-05-01 00:00:00'
AND net_name LIKE '%已经%'

EXPLAIN SELECT NAME, age FROM my_table WHERE age > 30;

-- 复合索引

ALTER TABLE `table_name` ADD INDEX index_name ( `column1`, `column2`, `column3` )