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https://dev.mysql.com/doc/refman/9.7/en/srjsapi-regressor.html
SignatureRegressor.train( Table trainData, String targetColumnName ) Arguments trainData (Table): A Table which contains a training dataset. The table must not exceed 10 GB in size, or contain more than 100 million rows or more than 1017 columns.
https://dev.mysql.com/doc/refman/9.7/en/timestamp-initialization.html
For any TIMESTAMP or DATETIME column in a table, you can assign the current timestamp as the default value, the auto-update value, or both: An auto-initialized column is set to the current timestamp for inserted rows that specify no value for the ...
https://dev.mysql.com/doc/refman/9.7/en/innodb-standard-monitor.html
The contents include the statement that failed as well as information about the constraint that failed and the referenced and referencing tables. The Lock Monitor is the same as the Standard Monitor except that it includes additional lock ...
https://dev.mysql.com/doc/refman/9.7/en/correlated-subqueries.html
A correlated subquery is a subquery that contains a reference to a table that also appears in the outer query. For example: SELECT * FROM t1 WHERE column1 = ANY (SELECT column1 FROM t2 WHERE t2.column2 = t1.column2); Notice that the subquery ...So, ...
https://dev.mysql.com/doc/ndbapi/en/ndb-start-mysql-data-types.html
This section provides information about the way in which MySQL data types are represented in NDBCLUSTER table columns and how these values can be accessed in NDB API applications. make_ndb_varchar(myVal, "NDB is way cool!!"); ...The MySQL TINYINT, ...
https://dev.mysql.com/doc/refman/9.7/en/invisible-indexes.html
ALTER INDEX operation: ALTER TABLE t1 ALTER INDEX i_idx INVISIBLE; ALTER TABLE t1 ALTER INDEX i_idx VISIBLE; Information about whether an index is visible or invisible is available from the Information Schema STATISTICS table or SHOW INDEX output.
https://dev.mysql.com/doc/refman/9.7/en/sys-statement-performance-analyzer.html
Parameters in_action ENUM('snapshot', 'overall', 'delta', 'create_tmp', 'create_table', 'save', 'cleanup'): The action to take. The default is to make a snapshot of the current content of the Performance Schema events_statements_summary_by_digest ...
https://dev.mysql.com/doc/refman/9.7/en/charset-unicode-conversion.html
In terms of table content, conversion from utf8mb3 to utf8mb4 presents no problems: For a BMP character, utf8mb4 and utf8mb3 have identical storage characteristics: same code values, same encoding, same length. In terms of table structure, these are ... This section describes issues that you may face when converting character data between the utf8mb3 and utf8mb4 character ...
https://dev.mysql.com/doc/refman/9.7/en/engine-condition-pushdown-optimization.html
Joins are not directly supported; conditions involving multiple tables are pushed separately where possible. Previously, engine condition pushdown was limited to terms referring to column values from the same table to which the condition was being ... This optimization improves the efficiency of direct comparisons between a nonindexed column and a ...
https://dev.mysql.com/doc/refman/9.7/en/group-by-optimization.html
The most general way to satisfy a GROUP BY clause is to scan the whole table and create a new temporary table where all rows from each group are consecutive, and then use this temporary table to discover groups and apply aggregate functions (if ...