84669 person learning
152542 person learning
20005 person learning
5487 person learning
7821 person learning
359900 person learning
3350 person learning
180660 person learning
48569 person learning
18603 person learning
40936 person learning
1549 person learning
1183 person learning
32909 person learning
索引过滤性不好是由什么原因引起的,应该怎么解决
学习是最好的投资!
That is, the column you indexed does not change much and has few distributed values, such as gender or order status. There is no need to build an index. It will not improve query efficiency but increase the insertion burden
That is, the column you indexed does not change much and has few distributed values, such as gender or order status. There is no need to build an index. It will not improve query efficiency but increase the insertion burden