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https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-internals.html
If you create a table when innodb_strict_mode is OFF, and a subsequent INSERT or UPDATE statement attempts to create an index entry that does not fit in the size of the compressed page, the operation fails with ERROR 42000: Row size too large. This ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-multi-versioning.html
If InnoDB generates a clustered index automatically, the index contains row ID values. In the InnoDB multi-versioning scheme, a row is not physically removed from the database immediately when you delete it with an SQL statement. InnoDB only ...It ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-transactions.html
This can be done by using the IGNORE INDEX index hint as part of the SELECT statement reading the table (see Section 10.9.4, “Index Hints”). This issue does not occur for queries that use index or table scans, even against NDB tables having BLOB ... A number of limitations exist in NDB Cluster with regard to the handling of ...
https://dev.mysql.com/doc/refman/8.4/en/create-table-foreign-keys.html
If the CONSTRAINT symbol clause is not defined, or a symbol is not included following the CONSTRAINT keyword, both InnoDB and NDB storage engines ignore FOREIGN_KEY index_name. MySQL requires indexes on foreign keys and referenced keys so that ...
https://dev.mysql.com/doc/refman/8.4/en/extensions-to-ansi.html
Use of CHANGE col_name, DROP col_name, or DROP INDEX, IGNORE or RENAME in ALTER TABLE statements. Use of index names, indexes on a prefix of a column, and use of INDEX or KEY in CREATE TABLE statements. For example, MySQL Server recognizes the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-change-buffer.html
The change buffer is a special data structure that caches changes to secondary index pages when those pages are not in the buffer pool. Figure 17.3 Change Buffer Unlike clustered indexes, secondary indexes are usually nonunique, and inserts into ...
https://dev.mysql.com/doc/refman/8.4/en/converting-tables-to-innodb.html
The InnoDB buffer pool caches both table data and index data, speeding up lookups for queries and keeping query results in memory for reuse. Handling Too-Long Or Too-Short Transactions Because MyISAM tables do not support transactions, you might not ... If you have MyISAM tables that you want to convert to InnoDB for better reliability and scalability, review the following guidelines and tips before ...
https://dev.mysql.com/doc/refman/8.4/en/mysqlslap.html
Invoke mysqlslap like this: mysqlslap [options] Some options such as --create or --query enable you to specify a string containing an SQL statement or a file containing statements. If you specify a file, by default it must contain one statement per ... mysqlslap is a diagnostic program designed to emulate client load for a MySQL server and to report the timing of each ...
https://dev.mysql.com/doc/workbench/en/wb-tutorial-visual-explain-dbt3.html
After reviewing the query again, consider that a multiple-column index can meet the conditions of the WHERE clause that is based on both the o_orderdate and o_clerk columns as the next statement shows. Next, an Explain report was generated by ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/mem-qanal-using-ui.html
By default, the Statements view displays the following: QRTi pie chart: visual representation of the Query Response Time index. Figure 32.1 Default Query Analyzer View Table 32.2 Controls of the default Query Analyzer view Control Description ... To ...