JDBC：是否最好使用executeBatch或executeUpdate来检查每个UPDATE语句是否成功？

Question

I have a MySQL database where I need to do a 1k or so updates, and I am contemplating whether it would be more appropriate to use executeBatch or executeUpdate . The preparedstatement is to be built on an ArrayList of 1k or more ids (which are PKs of the table to be updated). For each update to the table I need to check if it was updated or not (it's possible that the id is not in the table). In the case that the id doesn't exist, I need to add that id to a separate ArrayList which will be used to do batch inserts.

Given the above, is it more appropriate to do:

1. Various separate executeUpdate() and then store the id if it is not updated, or

2. Simply create a batch and use executeBatch() , which will return an array of either a 0 or 1 for each separate statement/id.

In case two, the overhead would be an additional array to hold all the 0 or 1 return values. In case one, the overhead would be due to executing each UPDATE separately.

Answer 1

我会批处理，因为除非您以某种方式在同一设备上运行网络延迟，否则就需要考虑网络延迟。

Answer 2

Definitely executeBatch(), and make sure that you add "rewriteBatchedStatements=true" to your jdbc connection string.

The increase in throughput is hard to exaggerate. Your 1K updates will likely take barely longer than a single update, assuming that you have proper indexes and a WHERE clause that makes use of them.

Without the extra setting on the connection string, the time to do the batch update is going to be about the same as to do each update individually.