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https://dev.mysql.com/doc/refman/8.4/en/information-schema-optimizer-trace-table.html
The OPTIMIZER_TRACE table has these columns: QUERY The text of the traced statement. The OPTIMIZER_TRACE table provides information produced by the optimizer tracing capability for traced statements. MISSING_BYTES_BEYOND_MAX_MEM_SIZE Each ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-partitions-table.html
PARTITION_COMMENT The text of the comment, if the partition has one. Each row in this table corresponds to an individual partition or subpartition of a partitioned table. The PARTITIONS table has these columns: TABLE_CATALOG The name of the catalog ...
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/information-schema-table-reference.html
The following table summarizes all available INFORMATION_SCHEMA tables. For greater detail, see the individual table descriptions. Table 28.1 INFORMATION_SCHEMA Tables Table Name Description Deprecated ADMINISTRABLE_ROLE_AUTHORIZATIONS Grantable ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-triggers-table.html
To see information about a table's triggers, you must have the TRIGGER privilege for the table. The TRIGGERS table has these columns: TRIGGER_CATALOG The name of the catalog to which the trigger belongs. TRIGGER_SCHEMA The name of the schema ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-backup.html
Dumped tables are stored into text files that are human-readable, so spotting table corruption becomes easier. The key to safe database management is making regular backups. Hot and cold backups are physical backups that copy actual data files, ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-benefits.html
The storage layout for table data is more efficient for BLOB and long text fields, with the DYNAMIC row format. InnoDB tables have the following benefits: If the server unexpectedly exits because of a hardware or software issue, regardless of what ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-usage.html
This setting may still be useful for tables with many long BLOB, VARCHAR or TEXT columns, because such values often do compress well, and might therefore require fewer overflow pages as described in Section 17.9.1.5, “How Compression Works for ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-file-defragmenting.html
Another way to perform a defragmentation operation is to use mysqldump to dump the table to a text file, drop the table, and reload it from the dump file. Random insertions into or deletions from a secondary index can cause the index to become ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-file-space.html
LONGBLOB and LONGTEXT columns must be less than 4GB, and the total row length, including BLOB and TEXT columns, must be less than 4GB. The data files that you define in the configuration file using the innodb_data_file_path configuration option ...