Why does MySQL forbid lock tables in stored procedures?
This is a pretty easy question and someone usually handles those before I need to step in as a backstop. The key why you cannot execute a LOCK TABLE command within a stored program is here: https://dev.mysql.com/doc/refman/5.7/en/lock-tables-and-transactions.html
How do you lock a table in MySQL?
LOCK TABLES table_name [ READ | WRITE] In this syntax, you specify the name of the table that you want to lock after the LOCK TABLES keywords. In addition, you specify the type of lock, either READ or WRITE. MySQL allows you to lock multiple tables by specifying a list of comma-separated names of tables with lock types that you want to lock
What are read and write locks in MySQL?
Read locks are “shared” locks which prevent a write lock is being acquired but not other read locks. Write locks are “exclusive ” locks that prevent any other lock of any kind. In this tutorial, you have learned how to lock and unlock tables for cooperating with the table accesses between sessions.
What does the lock flag mean in MySQL?
A lock is a flag associated with a table. MySQL allows a client session to explicitly acquire a table lock for preventing other sessions from accessing the same table during a specific period.
How to get a lock in MySQL Message Table?
In the first session, first, connect to the database and use the CONNECTION_ID () function to get the current connection id as follows: Then, insert a new row into the messages table. Next, query the data the messages table. After that, acquire a lock using the LOCK TABLE statement. Finally, try to insert a new row into the messages table:
What happens when transaction within a stored procedure fails?
When you open a transaction, and a query inside it fails, the transaction keeps open, it does not commit nor rollback the changes. So BE CAREFUL, any table/row that was locked with a previous query like SELECT