Configuring Persistent Optimizer Statistics Parameters. Configuring the Merge Threshold for Index Pages. InnoDB Table Compression. Overview of Table Compression. Creating Compressed Tables. InnoDB Page Compression. Enabling File Formats. Verifying File Format Compatibility. Identifying the File Format in Use. Modifying the File Format. Defragmenting a Table. Online DDL Operations. Online DDL Limitations. Using the Compression Information Schema Tables. Enabling InnoDB Monitors.
InnoDB Backup and Recovery. Benefits of the InnoDB memcached Plugin. InnoDB memcached Architecture. InnoDB memcached Plugin Internals. Troubleshooting the InnoDB memcached Plugin. Forcing InnoDB Recovery.
For the single-table syntax, the UPDATE statement updates columns of existing rows in the named table with new values. Isolation is the I in the acronym ACID; the isolation level is the setting that fine-tunes the balance between performance and reliability, consistency, and reproducibility of results when multiple transactions are making changes and performing queries at the same time. Does select statement lock the rows? What is row level locking in MySQL? If the tables use InnoDB, MySQL automatically uses row level locking so that multiple transactions can use same table simultaneously for read and write, without making each other wait.
What is read lock in MySQL? In addition, other sessions can read data from the table without acquiring the lock. The session that holds the READ lock can only read data from the table, but cannot write. Where is current? It allows you to perform positioned updates and deletes on updatable cursors. What is row lock in Oracle? A row lock, also called a TX lock, is a lock on a single row of table.
Oracle Database automatically places an exclusive lock on the updated row and a subexclusive lock on the table. Short answers: Q1: Yes. Q2: Doesn't matter which you use. Long answer: A select Which MySQL data type to use for storing boolean values.
How to get the sizes of the tables of a MySQL database?
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