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https://dev.mysql.com/doc/refman/8.4/en/drop-index.html
algorithm_option: ALGORITHM [=] {DEFAULT | INPLACE | COPY} lock_option: LOCK [=] {DEFAULT | NONE | SHARED | EXCLUSIVE} DROP INDEX drops the index named index_name from the table tbl_name. This statement is mapped to an ALTER TABLE statement to drop ...This is done automatically by the server whenever it determines that it is possible to do so; you do not have to use any special SQL syntax or server options to cause it to ...
https://dev.mysql.com/doc/refman/8.4/en/events-privileges.html
Since the user does not have the INSERT privilege for the table in question, the event has no effect. If you inspect the MySQL error log (hostname.err), you can see that the event is executing, but the action it is attempting to perform fails: ...
https://dev.mysql.com/doc/refman/8.4/en/example-auto-increment.html
To start with an AUTO_INCREMENT value other than 1, set that value with CREATE TABLE or ALTER TABLE, like this: mysql> ALTER TABLE tbl AUTO_INCREMENT = 100; InnoDB Notes For information about AUTO_INCREMENT usage specific to InnoDB, see Section ...
https://dev.mysql.com/doc/refman/8.4/en/identifier-length.html
The following table describes the maximum length for each type of identifier. For constraint definitions that include no constraint name, the server internally generates a name derived from the associated table name. For example, internally ...You ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-buffer-pool-resize.html
Before you change innodb_buffer_pool_chunk_size, calculate the effect on innodb_buffer_pool_size to ensure that the resulting buffer pool size is acceptable. Monitoring Online Buffer Pool Resizing Progress The Innodb_buffer_pool_resize_status ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-buffer-pool.html
The buffer pool is an area in main memory where InnoDB caches table and index data as it is accessed. A table scan, performed for a mysqldump operation or a SELECT statement with no WHERE clause, for example, can bring a large amount of data into ...The buffer pool permits frequently used data to be accessed directly from memory, which speeds up ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-change-buffer.html
On disk, the change buffer is part of the system tablespace, where index changes are buffered when the database server is shut down. Configuring Change Buffering When INSERT, UPDATE, and DELETE operations are performed on a table, the values of ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-understanding-innodb-locking.html
When a transaction updates a row in a table, or locks it with SELECT FOR UPDATE, InnoDB establishes a list or queue of locks on that row. Similarly, InnoDB maintains a list of locks on a table for table-level locks. If a second transaction wants to ...At any given time, a transaction may request a lock that is held by another transaction, in which case it is blocked by that other ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-optimizer-statistics.html
This section describes how to configure persistent and non-persistent optimizer statistics for InnoDB tables. Persistent optimizer statistics also provide control and flexibility with these additional benefits: You can use the ...Persistent ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-ftdump.html
It reads the MyISAM index file directly, so it must be run on the server host where the table is located. Before using myisam_ftdump, be sure to issue a FLUSH TABLES statement first if the server is running. Invoke myisam_ftdump like this: ...