| Hibernate 4.3.5 was executing "SHOW FULL TABLES and SHOW FULL COLUMNS with LIKE '%' " in order to discover the complete database tables columns. Hibernate 5.2.1 is no longer using "%" but it is giving as parameter all individual columns from every table it discovered. The amount of queries to the database during startup increased from ~200 to ~2700. Due to the constant load to which the server is exposed from other applications, each query takes 100-150ms, thus increasing the startup time of our application from 10-20 seconds to 4-5 minutes.
The number of queries can be easily seen by enabling MySQL query log. |