mysql模糊查询%我就不多说了。想要%不在左边也能用到索引，可以选择加全文索引
假设我的表是wa_log记录日志的，url是访问的路径，想要查询url路径中包含admin的数据
ALTER TABLE wa_log ADD FULLTEXT(url);
EXPLAIN SELECT * FROM wa_log WHERE MATCH(url) AGAINST ('admin' IN BOOLEAN MODE);
ALTER TABLE wa_log ADD FULLTEXT(url);
EXPLAIN SELECT * FROM wa_log WHERE MATCH(url) AGAINST ('admin' IN BOOLEAN MODE);