Search Results
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-session-temp-tablespaces-table.html
Session temporary tablespaces are recreated each time the server is started. Space IDs are not persisted when the server is shut down and may be reused. ACTIVE indicates that the tablespace is currently used by a session. INACTIVE indicates that the ... The INNODB_SESSION_TEMP_TABLESPACES table provides metadata about session temporary tablespaces used for internal and user-created temporary ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-tls-channel-status-table.html
For each channel, the row with a PROPERTY value of Enabled indicates whether the channel supports encrypted connections, and other channel rows indicate TLS context properties: For mysql_main, the Enabled property is yes or no to indicate whether ...
https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
null-values: A number between 0.0 and 1.0 indicating the fraction of column values that are SQL NULL values. The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query ...The column_statistics table has these characteristics: The table contains statistics for columns of all data types except geometry types (spatial data) and ...
https://dev.mysql.com/doc/refman/8.4/en/declare-condition.html
It can take the following forms: mysql_error_code: An integer literal indicating a MySQL error code. Do not use MySQL error code 0 because that indicates success rather than an error condition. For a list of MySQL error codes, see Server Error ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-operations.html
When you create a UNIQUE or PRIMARY KEY index, MySQL must do some extra work. For UNIQUE indexes, MySQL checks that the table contains no duplicate values for the key. Adding a primary key using ALGORITHM=INPLACE is only permitted when the SQL_MODE ...For a PRIMARY KEY index, MySQL also checks that none of the PRIMARY KEY columns contains a ... Online support details, syntax ...
https://dev.mysql.com/doc/relnotes/mysql-cluster/8.4/en/news-8-4-5.html
MySQL NDB Cluster 8.4.5 is a new LTS release of NDB 8.4, based on MySQL Server 8.4 and including features in version 8.4 of the NDB storage engine, as well as fixing recently discovered bugs in previous NDB Cluster releases. This variable provides ...NDB Cluster 8.4 source code and binaries can be obtained from ...Compilation Notes Functionality Added or Changed Bugs Fixed Compilation Notes The ability to build the source without NDB using the internal script storage/ndb/compile-cluster was adversely affected by work done ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-metadata-locks-table.html
MySQL uses metadata locking to manage concurrent access to database objects and to ensure data consistency; see Section 10.11.4, “Metadata Locking”. Locks that have been requested but not yet granted (shows which sessions are waiting for which ...Metadata locking applies not just to tables, but also to schemas, stored programs (procedures, functions, triggers, scheduled events), tablespaces, user locks acquired with the GET_LOCK() function (see Section 14.14, “Locking Functions”), and locks acquired with the locking service described in Section 7.6.9.1, “The Locking ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-logs-cluster-log.html
Table 25.25 Common NDB cluster log messages Log Message Description Event Name Event Type Priority Severity Node mgm_node_id: Node data_node_id Connected The data node having node ID node_id has connected to the management server (node mgm_node_id).
https://dev.mysql.com/doc/c-api/8.4/en/c-api-asynchronous-interface-usage.html
The asynchronous C API functions cover operations that might otherwise block when reading to or writing from the server connection: The initial connection operation, sending a query, reading the result, and so forth. mysql_real_query_nonblocking(): ...Each asynchronous function has the same name as its synchronous counterpart, plus a _nonblocking suffix: mysql_fetch_row_nonblocking(): Asynchronously fetches the next row from the result ...
https://dev.mysql.com/doc/refman/8.4/en/char.html
The server SQL mode has no effect on comparison behavior with respect to trailing spaces. The CHAR and VARCHAR types are declared with a length that indicates the maximum number of characters you want to store. When CHAR values are retrieved, ...