Arthas is an open source tool for Java developed by Alibaba recently. It mainly for diagnosing the problems of java. I. Overview This tool can help you do the following things: Which jar package loaded this class from? Why do you code throws various kinds of Exceptions? If you encounter problems on product environment , […]
Month: August 2019
Mysql delete duplicate records and only keep one row
Recently, I have been working for a subject storehouse system. Since duplicate subject are added to the storehouse, it is necessary to query the duplicate subject, and delete all duplicate subject leave only one, so that the duplicate subject cannot be taken when the test is taken. First wrote a small example: Single field operation […]