How to speed up database update

You don't have to worry about how to increase the speed of database update .. See the following SQL statement.

[Java] String SQL = "update cats set name_alias = '" + rs. getString (1) + "'where name = '" + rs. getString (1) + "'";

 

If the data volume is small, there will certainly be no problem. It will be updated in the twinkling of an eye. However, if a table is larger than a few millions of records, tens of thousands of records would have taken an hour. The solution is that the fields in the where condition must be indexed. Generally, you can directly use the primary index of the table. For example, in the following SQL statement, id is the primary index.

[Java] String SQL = "update cats set name_alias = '000000' where id = '" + rs. getInt (1) + "'";

 

After this optimization, the update speed will increase significantly, and tens of thousands of update operations can be completed in just a few minutes.