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https://dev.mysql.com/doc/refman/8.4/en/semijoins-antijoins.html
For an inner join between two tables, the join returns a row from one table as many times as there are matches in the other table. Assuming that class_num is a primary key in the class table, duplicate suppression is possible by using SELECT ... A ...
https://dev.mysql.com/doc/refman/8.4/en/sys-statement-performance-analyzer.html
statement_performance_analyzer.limit, @sys.statement_performance_analyzer.limit The maximum number of rows to return for views that have no built-in limit. mysql> CALL sys.statement_performance_analyzer('delta', 'mydb.tmp_digests_ini', ... Creates a ...
https://dev.mysql.com/doc/connector-net/en/connector-net-programming-tracing-mysql-custom-listeners.html
NoIndex = 1, BadIndex = 2, SkippedRows = 3, SkippedColumns = 4, FieldConversion = 5. To build custom listeners that work with the MySQL Connector/NET Trace Source, it is necessary to understand the key methods used, and the event data formats used.
https://dev.mysql.com/doc/internals/en/position.html
Purpose Provide the MySQL server with position/offset information for last-read row. ref_length in the above case is the size needed to store current_position. If you are using offsets to mark rows, then current_position should be the offset.
https://dev.mysql.com/doc/ndbapi/en/ndb-examples-basic-read.html
This example illustrates basic retrieval of one or more rows from an NDB table using the NdbRecord interface and an NdbScanOperation. We assume that you have already created and populated the basic table, perhaps using the row insertion example ...
https://dev.mysql.com/doc/ndbapi/en/overview-ndbinterpretedcode-using.html
Method Buffer (words) Request message (words) load_const_null() 1 1 load_const_u16() 1 1 load_const_u32() 2 2 load_const_u64() 3 3 NdbInterpretedCode Methods for Copying Values Between Registers and Table Columns NdbInterpretedCode provides two ...
https://dev.mysql.com/doc/refman/8.4/en/delete-optimization.html
To delete rows more quickly, you can increase the size of the key cache by increasing the key_buffer_size system variable. The time required to delete individual rows in a MyISAM table is exactly proportional to the number of indexes. To delete all ...Truncate operations are not transaction-safe; an error occurs when attempting one in the course of an active transaction or active table ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-data-encryption.html
row *************************** SPACE: 4294967294 NAME: mysql SPACE_TYPE: General ENCRYPTION: Y *************************** 2. row *************************** SPACE: 2 NAME: test/t1 SPACE_TYPE: Single ENCRYPTION: Y *************************** 3. row ... InnoDB supports data-at-rest encryption for file-per-table tablespaces, general tablespaces, the mysql system tablespace, redo logs, and undo ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-disk-data-storage-requirements.html
For each row, this is equal to the space required to store the largest possible value for that column. Each row in a Disk Data table uses 8 bytes in memory to point to the data stored on disk. For example, converting a CHAR(4) column from ... The ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-prepared-statements-instances-table.html
To control the size of this table, set the performance_schema_max_prepared_statements_instances system variable at server startup. If the statement is successfully instrumented, a new row is added to the prepared_statements_instances table. Prepared ... The Performance Schema provides instrumentation for prepared statements, for which there are two protocols: The binary ...