SQL分析工具
EXPLAIN SELECT * FROM invitation_assist_flow WHERE seller_id = 1 AND activity_id = 1 AND marketing_type = 1 AND new_user_id = 1 AND new_user_mobile = '1' AND old_user_id = 1 AND old_user_mobile = '1'
分析:
可能使用了五种索引,涉及到2条数据,当涉及的数量大于75%左右时(自己用少数量测试)过多时,此时就会全表查,索引就会失效