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https://dev.mysql.com/doc/refman/8.4/en/innodb-error-handling.html
To have the entire transaction roll back, start the server with --innodb-rollback-on-timeout enabled. A duplicate-key error rolls back the SQL statement, if you have not specified the IGNORE option in your statement. InnoDB sometimes rolls back only ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-system-tables.html
The first index is GEN_CLUST_INDEX, which is a clustered index created by InnoDB if the table does not have a user-defined clustered index. row *************************** TABLE_ID: 71 NAME: test/t1 STATS_INITIALIZED: Initialized NUM_ROWS: 1 ... You ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-locking.html
Shared and Exclusive Locks Intention Locks Record Locks Gap Locks Next-Key Locks Insert Intention Locks AUTO-INC Locks Predicate Locks for Spatial Indexes Shared and Exclusive Locks InnoDB implements standard row-level locking where there are two ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-locks-set.html
If you have no indexes suitable for your statement and MySQL must scan the entire table to process the statement, every row of the table becomes locked, which in turn blocks all inserts by other users to the table. It does have an effect for tables ... A locking read, an UPDATE, or a DELETE generally set record locks on every index record that is scanned in the processing of an SQL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-next-key-locking.html
The so-called phantom problem occurs within a transaction when the same query produces different sets of rows at different times. For example, if a SELECT is executed twice, but returns a row the second time that was not returned the first time, ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-limitations.html
The transactions that hold metadata locks on the table may have been started before or during the online DDL operation. Tables created before MySQL 5.6 that include temporal columns (DATE, DATETIME or TIMESTAMP) and have not been rebuilt using ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-operations.html
ALGORITHM=INPLACE is not permitted under certain conditions if columns have to be converted to NOT NULL. The server prohibits changes to foreign key columns that have the potential to cause loss of referential integrity. Online support details, ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-performance.html
Due to the exclusive metadata lock requirements outlined above, an online DDL operation may have to wait for concurrent transactions that hold metadata locks on the table to commit or rollback. Online DDL improves several aspects of MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-read-only-instance.html
The instance must have performed a slow shutdown before being put into the read-only state. Changes to configuration option settings that would normally change the behavior of write operations, have no effect when the server is in read-only mode.
https://dev.mysql.com/doc/refman/8.4/en/innodb-statistics-estimation.html
Enabling innodb_stats_on_metadata may reduce access speed for schemas that have a large number of tables or indexes, and reduce stability of execution plans for queries that involve InnoDB tables. If your database has many large tables, consider ...