Once I turned on the logs of slow queries and noticed that the time is being written with the wrong time zone.Continue reading “MySQL. Time mismatch in error logs and slow queries logs”
I will give an example of changing join_buffer_size in MySQL.
join_buffer_size determines the size of the buffer for index scanning and joins without indexes. I recommend adding indexes or slightly increasing join_buffer_size (but in this case a full table scan will be performed).
Enabling slow_query_log and log_queries_not_using_indexes will help to identify slow queries and queries without indexes that affect the performance of the MySQL server.Continue reading “How to enable Slow Query Log in MySQL”
In order to see the process of exporting a database to an SQL file, you can use the Pipe Viewer utility.Continue reading “How to see the process of exporting a SQL file?”
MySQL triggers are procedures that fire when certain events occur, such as inserting, deleting, changing a string.Continue reading “Triggers in MySQL”
I noticed once when executing a SQL query the following error:Continue reading “Resolving error #1064 – You have an error in your SQL syntax”
For example, update the MySQL server from version 5.5 to 5.7.
Before performing an update, it is imperative that you make backup copies of all databases, including the standard ones.
Once, after the power was turned off, the UPS was discharged, then the generator automatic start did not work because it turned on and off several times, as a result, the server with MySQL was also started and disconnected from the power supply several times, later the tables of different databases were damaged , including the default database with mysql users, as a result, the MySQL daemon did not start.Continue reading “Recovering MySQL InnoDB after power failure”
InnoDB log file size – the size of the transaction log files that are needed to cancel transactions and restore the database in case of failure.Continue reading “Changing InnoDB log file size in MySQL”
I will give an example of resizing the InnoDB buffer pool in MySQL.
In the InnoDB buffer pool, this is the memory space in which indexes, caches, buffers, etc. are stored.