Incorrect MySQL database parameter setting causes app not to connect issues

OA (Tomcat+mysql) Some recent problems, Friday, please factory technology remote debugging a bit. The debugging process is as follows:

1. The index of OA database is optimized;

2. Change the database minimum connection number from the original 30 to 5;

3. Modify MySQL database parameters, add transaction-isolation = Read Committed.

Since debugging is working time, the database and application are not restarted after the modification is completed. Saturday morning I restarted, but always restart failure, manufacturers of technical contact is not. Had to solve their own.

Reviewing some of his changes, the 12th does not cause the application to start, it appears that there is only a third article. Looked at the Tomcat startup log, found that the database connection is not on, but the database is normal startup Ah, but why not connect it?

Comment out the added parameters, restart the database, start the application, and find out. What is this for?

It suddenly occurred to me that in order to make the decision from the replication, the database started the log mode, then it will be the two conflicts? After searching, I saw the format of the log pattern and some relationships before the transaction:

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The log mode defaults to statement, and my database was used by default, which appears to be a conflict between the log pattern and the transaction level. Modify the database configuration file again to modify the log mode:

Binlog_format=mixed

Transaction-isolation = Read Committed

Restart the database and start the application without any problems.

Incorrect MySQL database parameter setting causes app not to connect issues