SELECT FOR UPDATE SPRING JDBCTEMPLATE HOW TO

If itвЂ™s a valid candidate, then processВ the data in the MSG_CONTENTВ column.

If not, ignore that row and release the row lock.

While going through each message data with row lock, check whether itвЂ™s a valid candidate to process based on the isValidToProcess()В method.

Go through each message ID one by one and get row lock for the respective message ID in each iteration.

Select message IDs to process based on the MSG_STATUSВ value 1.So our execution flow would be like this: The VENDOR_ID value will be used to do the filtering logic in the isValidToProcess() method. For this example, letвЂ™s consider that we should process the message data with status value 1 and once itвЂ™s processed, we should set that value toВ 2В to mark it as a processed row. MSG_STATUS refers to an enum which represents the status of the message life cycle - whether itвЂ™s processed or not.

Our example message table schema would be like this: CREATE TABLE MSG_DATA In the possible candidate row selection criteria for processing, there are some conditions that can be included in the SQL statement itself via the WHEREВ clause, but there are some other conditions which cannot be included in the SQL query - to make it easy, letвЂ™s assume that these additional conditions evaluation logic is encapsulated using a method called isValidToProcess(). While processing data, it will transform the message content as well as change the state of the message to PROCESSEDВ to mark it as a completed message. Threads in this thread pool will periodically poll the database to select possible candidate rows to process. BackgroundДЄs the example use case for this blog post, letвЂ™s consider that we have a database table with message data that should be processed concurrently using a Java thread pool.

SELECT FOR UPDATE SPRING JDBCTEMPLATE HOW TO

If you have already done it, believe me, you are going to learn how to do it correctly without getting any stale locks and how to troubleshoot stale locks (for incorrect usage of row-locking) at the Oracle side. In this blog post, IвЂ™m going to explain how to use Spring JDBC with the row-locking feature of Oracle database to maintain the synchronization of concurrent data processing tasks that are expected to transform some data and persist it back to the database. Although itвЂ™s a great feature, it can lead to critical scenarios like your system being stuck due to stale locks on the database side. Database row-locking is one of the great features provided by RDBMS vendors to manage synchronization of concurrent data processing activities on a given table.

Select for update spring jdbctemplate