Search Results
https://dev.mysql.com/doc/refman/8.4/en/bit-value-literals.html
A leading 0b is case-sensitive and cannot be written as 0B. In numeric contexts, MySQL treats a bit literal like an integer. To ensure numeric treatment of a bit literal, use it in numeric context. For example, a bit literal assigned to a ...
https://dev.mysql.com/doc/refman/8.4/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 ...
https://dev.mysql.com/doc/refman/8.4/en/forcing-innodb-recovery.html
To investigate database page corruption, you might dump your tables from the database with SELECT ... Usually, most of the data obtained in this way is intact. Serious corruption might cause SELECT * FROM tbl_name statements or InnoDB background ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-views-table.html
You must have the SHOW VIEW privilege to access this table. The VIEWS table has these columns: TABLE_CATALOG The name of the catalog to which the view belongs. TABLE_SCHEMA The name of the schema (database) to which the view belongs. VIEW_DEFINITION ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-file-defragmenting.html
Random insertions into or deletions from a secondary index can cause the index to become fragmented. Fragmentation means that the physical ordering of the index pages on the disk is not close to the index ordering of the records on the pages, or ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-locks-per-fragment.html
The locks_per_fragment table provides information about counts of lock claim requests, and the outcomes of these requests on a per-fragment basis, serving as a companion table to operations_per_fragment and memory_per_fragment. This table also ...
https://dev.mysql.com/doc/refman/8.4/en/mysqldumpslow.html
The MySQL slow query log contains information about queries that take a long time to execute (see Section 7.4.5, “The Slow Query Log”). mysqldumpslow parses MySQL slow query log files and summarizes their contents. Normally, mysqldumpslow ...
https://dev.mysql.com/doc/refman/8.4/en/operator-precedence.html
Operator precedences are shown in the following list, from highest precedence to the lowest. Operators that are shown together on a line have the same precedence. When used as a comparison operator, it has the same precedence as <=>, >=, >, <=, <, ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-character.html
For character and string columns, follow these guidelines: Use binary collation order for fast comparison and sort operations, when you do not need language-specific collation features. You can use the BINARY operator to use binary collation within ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-asynchronous-connection-failover-table.html
This table holds the replica's source lists for each replication channel for the asynchronous connection failover mechanism. The asynchronous connection failover mechanism automatically establishes an asynchronous (source to replica) replication ...