I’m trying to learn to use Hibernate using MySQL, I’ve never worked with it before and after a chain of errors I finally get stucked with this: I’ve tried with possible solutions of another questions, but nothing, it doesn’t work. This is what I’ve done so far: hibernate.cfg.xml …
Tag: mysql
API service works every second request
I have problem with jax-rs REST service. Service does not operate properly. Every second request service throw me exception: HTTP Status 500 – could not execute query type Exception report message …
MySQL Batchupdate() with ON DUPLICATE KEY UPDATE
I am using batchUpdate() to insert multiple records in a table. As per the requirement, if there is a duplicate value for a primary key while inserting it should be updated with the latest received data, hence I was trying to use ON DUPLICATE KEY UPDATE in INSERT statement. The ON DUPLICATE KEY UPDATE works g…
How do insert a file like this into a MySQL Database
This the file I am trying to store in the database. I want to get the title and comments stored. I do get it in, but it stores only the first line. Please help, not really good with databases. Answer You first need to split line into Title and Comment and assign an id. Try this (note it is case
Draw an ERD from Hibernate Mapping Files
I know it’s possible to reverse engineer from the database into mapping files but does anyone know if it’s possible to get hibernate to draw an ERD based on its own mapping files so that I can compare Hibernate’s ERD with the Databases one? Answer I achieved this by using: in my hibernate.cf…
What is the reason for OutOfMemoryError: Java heap space in the following case?
The following code sample is inside a for loop that runs about 2 million times. stack trace: Please let me know if more information is required. Thank you. Thanks everyone for the answers. I will accept BalusC’s answer since he answered first. Unfortunately I cant upvote any other answers due to not eno…
How to change MySQL timezone in a database connection using Java?
MySQL runs with timezone “GMT+8”, but Tomcat with “GMT”. When I save datetime to my database, everything seems to be OK, but when I check the datetime value in the database, I see the “GMT” value. Also when I try get the value from the database the value is changed, seems l…
Java: Insert multiple rows into MySQL with PreparedStatement
I want to insert multiple rows into a MySQL table at once using Java. The number of rows is dynamic. In the past I was doing… I’d like to optimize this to use the MySQL-supported syntax: but with a PreparedStatement I don’t know of any way to do this since I don’t know beforehand how m…
Want to store Object in MySQL database
I have a variable in java which return type is Object(java.lang.Object). I want to store this variable value in MySQL database without casting in any other primitive data type. Is there any data type available in MySQL related to Object? Answer You can use a BLOB to store the raw data, but otherwise no, MySQL…
Connect to remote MySQL database through SSH using Java
How can I connect to remote MySQL database through SSH from java application? Small code example is helpful for me and I’d appreciate this. Answer My understanding is that you want to access a mysql server running on a remote machine and listening on let’s say port 3306 through a SSH tunnel. To cr…