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https://dev.mysql.com/create-table.html
For CHAR, VARCHAR, BINARY, and VARBINARY columns, indexes can be created that use only the leading part of column values, using col_name(length) syntax to specify an index prefix length. CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name ...
https://dev.mysql.com/delete.html
DELETE QUICK is not useful when deleted values lead to underfilled index blocks spanning a range of index values for which new inserts occur again. In this case, use of QUICK can lead to wasted space in the index that remains unreclaimed. DELETE is ...
https://dev.mysql.com/glossary.html
InnoDB does not use the beta designation, preferring an early adopter phase that can extend over several point releases, leading to a GA release. index prefix In an index that applies to multiple columns (known as a composite index), the initial or ... These terms are commonly used in information about the MySQL database ...
https://dev.mysql.com/group-replication-options.html
Warning Use caution when enabling this option as incorrect usage can lead to conflicts in the group and rollback of transactions. Starting two servers or restarting one server with this option set while the group is running may lead to an artificial ... This section lists the system variables that are specific to the Group Replication ...
https://dev.mysql.com/innodb-compression-internals.html
Files are typically divided into fixed-size blocks that are compressed into variable-size blocks, which easily leads into fragmentation. Depending on the workload, this smaller database can in turn lead to a reduction in I/O, and an increase in ...
https://dev.mysql.com/innodb-compression-tuning.html
If the system performs DML operations on compressed tables, and the way the data is distributed leads to expensive compression failures at runtime, you might adjust additional advanced configuration options. If the compressed page size is set too ...
https://dev.mysql.com/innodb-parameters.html
Otherwise, statistics may be recalculated frequently which can lead to variations in query execution plans. System variables that are true or false can be enabled at server startup by naming them, or disabled by using a --skip- prefix. For example, ...
https://dev.mysql.com/json.html
For paths used in MySQL JSON functions, the scope is always the document being searched or otherwise operated on, represented by a leading $ character. The JSON data type provides these advantages over storing JSON-format strings in a string column: ...
https://dev.mysql.com/myisampack.html
pre-space The number of decimal columns that are stored with leading spaces. In this case, each value contains a count for the number of leading spaces. When the table is used later, the server reads into memory the information needed to decompress ...
https://dev.mysql.com/mysql-cluster-replication-conflict-resolution.html
A value that is too small can result in false positives, while one that is too large could lead to excessive wasted space in the database. This means that further conflicts during the propagation of any subsequent realignment operations will not be ... When using a replication setup involving multiple masters (including circular replication), it is possible that different masters may try to update the same row on the slave with different ...
Document created the 26/06/2006, last modified the 26/10/2018
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