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https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-performance-page-database-file-io.html
Table 5.2 Database File I/O By Host NameDescription Host The host from which the client connected. Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a ...
https://dev.mysql.com/doc/internals/en/tracing-example.html
} ] /* items */, "resulting_clause_is_simple": true, "resulting_clause": "`test`.`alias1`.`col_int_key`" So we get a shorter ORDER BY clause - and this is not visible in EXPLAIN or EXPLAIN EXTENDED!! This simplification can be worth it: this shorter ...The statement's execution is naturally made of "steps": "steps": [ { "join_preparation": { This is a join's preparation "select#": 1, for the first SELECT of the statement (which has only one, ...
https://dev.mysql.com/doc/internals/en/x-protocol-messages-messages.html
Returns Mysqlx.Resultset:: message Update { required Collection collection = 2; optional DataModel data_model = 3; optional Mysqlx.Expr.Expr criteria = 4; repeated Mysqlx.Datatypes.Scalar args = 8; optional Limit limit = 5; repeated Order order = 6; ... Topics in this section: Message Structure Message Sequence Common Messages Connection Session Expectations CRUD SQL Result Sets Expressions Data Types This section provides detailed information about how X Protocol defines ...
https://dev.mysql.com/doc/workbench/en/wb-preferences-sql-editor.html
This section provides configuration options that affect the SQL editor functionality in MySQL Workbench. Permits saving and reloading the SQL editor tabs after MySQL Workbench is closed and reopened (including after an unexpected shutdown).
https://dev.mysql.com/doc/workbench/en/wb-data-modeling-menus.html
Some menu items are not available in the MySQL Workbench Community Edition of this application, and are available only in the MySQL Workbench Commercial Editions. 9.1.1.1.1 The File Menu Use the File menu to open a project, begin a new project, or ...
https://dev.mysql.com/doc/x-devapi-userguide/en/method-chaining.html
X DevAPI supports a number of modern practices to make working with CRUD operations easier and to fit naturally into modern development environments. This section explains how to use method chaining instead of working with SQL strings of JSON ...
https://dev.mysql.com/doc/internals/en/optimizer-group-by-related-conditions.html
For the case GROUP BY x ORDER BY x, the optimizer will realize that the ORDER BY is unnecessary, because the GROUP BY comes out in order by x. Because DISTINCT is not always transformed to GROUP BY, do not expect that queries with DISTINCT will ...
https://dev.mysql.com/doc/internals/en/optimizer-partition-pruning.html
Each index is described by an ordered list of the columns which it covers: (keypart1, keypart2, ..., keypartN) For partition pruning, Range Analyzer is invoked with the WHERE clause and a list of table columns used by the partitioning and ...
https://dev.mysql.com/doc/internals/en/connection-phase-packets.html
Protocol::Handshake Initial Handshake Packet When the client connects to the server the server sends a handshake packet to the client. Depending on the server version and configuration options different variants of the initial packet are sent. To ...
https://dev.mysql.com/doc/mysql-errors/8.4/en/server-error-reference.html
A deadlock occurs when requests for locks arrive in inconsistent order between transactions. SELECT is unsafe because the order in which rows are retrieved by the SELECT determines which (if any) rows are ignored. This order cannot be predicted and ... The MySQL server writes some error messages to its error log, and sends others to client ...