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https://dev.mysql.com/doc/refman/8.4/en/partitioning-list.html
In MySQL 8.4, all rows relating to employees working at stores in that region can be deleted with the query ALTER TABLE employees TRUNCATE PARTITION pWest, which can be executed much more efficiently than the equivalent DELETE statement DELETE FROM ...For more detailed syntactical information, see Section 15.1.20, “CREATE TABLE ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-limitations.html
The ALTER TABLE clause LOCK=NONE is not permitted if there are ON...CASCADE or ON...SET NULL constraints on the table. When running an in-place online DDL operation, the thread that runs the ALTER TABLE statement applies an online log of DML ... The ...When the DML operations are applied, it is possible to encounter a duplicate key entry error (ERROR 1062 (23000): Duplicate entry), even if the duplicate entry is only temporary and would be reverted by a later entry in the online ...
https://dev.mysql.com/doc/refman/8.4/en/replication-solutions-diffengines.html
Instead, use ALTER TABLE to change the table types after the replica has been started. Start the replication process again: mysql> START REPLICA; Although the default_storage_engine variable is not replicated, be aware that CREATE TABLE and ALTER ...
https://dev.mysql.com/doc/refman/8.4/en/charset-conversion.html
To convert a binary or nonbinary string column to use a particular character set, use ALTER TABLE. The following statement accomplishes this: ALTER TABLE t MODIFY col1 CHAR(50) CHARACTER SET utf8mb4; Conversion may be lossy if the column contains ...Suppose that a table t has a binary column named col1 defined as ...For successful conversion to occur, one of the following conditions must apply: If the column has a binary data type (BINARY, VARBINARY, BLOB), all the values that it contains must be encoded using a ...
https://dev.mysql.com/doc/refman/8.4/en/known-issues.html
If you use ALTER TABLE to add a UNIQUE index to a table used in a MERGE table and then add a normal index on the MERGE table, the key order is different for the tables if there was an old, non-UNIQUE key in the table. This is because ALTER TABLE ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam-bulk-data-loading.html
For a MyISAM table, you can use concurrent inserts to add rows at the same time that SELECT statements are running, if there are no deleted rows in middle of the data file. With some extra work, it is possible to make LOAD DATA run even faster for a ... These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT ...
https://dev.mysql.com/doc/heatwave-aws/en/heatwave-aws-bulk-ingest-limitations.html
If needed, use ALTER TABLE to change the table's row format after running LOAD DATA FROM S3 with ALGORITHM=BULK. Bulk Ingest Limitations 7.2.2.3 Bulk Ingest Limitations The following are some limitations to the Bulk Ingest Feature of MySQL HeatWave ...If needed, set the secondary engine after running LOAD DATA FROM S3 with ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-statistics-table.html
However, prefix lengths for index specifications in CREATE TABLE, ALTER TABLE, and CREATE INDEX statements are interpreted as number of characters for nonbinary string types (CHAR, VARCHAR, TEXT) and number of bytes for binary string types (BINARY, ...The information_schema_stats_expiry system variable defines the period of time before cached table statistics ...
https://dev.mysql.com/doc/refman/8.4/en/index-statistics.html
(This may occur for bulk inserts or deletes, or some ALTER TABLE statements, for example.) If this happens, the statistics are collected using whatever value innodb_stats_method or myisam_stats_method has at the time. Storage engines collect ...For ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-analyze-table-complexity.html
To set the number of pages sampled for an individual table, use the STATS_SAMPLE_PAGES option with CREATE TABLE or ALTER TABLE. ANALYZE TABLE complexity for InnoDB tables is dependent on: The number of pages sampled, as defined by ...Note ...