PDF (US Ltr)
- 35.1Mb
PDF (A4)
- 35.2Mb
Man Pages (TGZ)
- 256.4Kb
Man Pages (Zip)
- 361.3Kb
Info (Gzip)
- 3.4Mb
Info (Zip)
- 3.4Mb
Search Results
https://dev.mysql.com/doc/refman/5.7/en/partitioning-limitations-locking.html
An UPDATE prunes locks only for tables on which no partitioning columns are updated. However, if an AUTO_INCREMENT value is generated for any partitioning column then all partitions are locked. ON DUPLICATE KEY UPDATE is pruned as long as no ...In ...
https://dev.mysql.com/doc/refman/5.7/en/performance-schema-mutex-instances-table.html
The mutex_instances table has these columns: NAME The instrument name associated with the mutex. The OBJECT_INSTANCE_BEGIN column is a property that uniquely identifies the mutex. When a thread attempts to lock a mutex, the events_waits_current ...
https://dev.mysql.com/doc/refman/5.7/en/performance-schema-processlist-table.html
This is the same value displayed in the Id column of the SHOW PROCESSLIST statement, displayed in the PROCESSLIST_ID column of the Performance Schema threads table, and returned by the CONNECTION_ID() function within the thread. For system user, ...
https://dev.mysql.com/doc/refman/5.7/en/performance-schema-replication-applier-status-by-coordinator-table.html
The replication_applier_status_by_coordinator table has these columns: CHANNEL_NAME The replication channel which this row is displaying. Issuing RESET MASTER or RESET SLAVE resets the values shown in these columns. All error codes and messages ...
https://dev.mysql.com/doc/refman/5.7/en/precision-math-expressions.html
In strict SQL mode, for INSERT into a column with an exact data type (DECIMAL or integer), a number is inserted with its exact value if it is within the column range. Inserts into numeric columns are affected by the SQL mode, which is controlled by ... With precision math, exact-value numbers are used as given whenever ...
https://dev.mysql.com/doc/refman/5.7/en/primary-key-optimization.html
The primary key for a table represents the column or set of columns that you use in your most vital queries. With the InnoDB storage engine, the table data is physically organized to do ultra-fast lookups and sorts based on the primary key column ...Query performance benefits from the NOT NULL optimization, because it cannot include any NULL ...
https://dev.mysql.com/doc/refman/5.7/en/range-optimization.html
The key_len column in the EXPLAIN output indicates the maximum length of the key prefix used. Equality Range Optimization of Many-Valued Comparisons Consider these expressions, where col_name is an indexed column: col_name IN(val1, ..., valN) ...
https://dev.mysql.com/doc/refman/5.7/en/replication-features-max-allowed-packet.html
If you are replicating large column values (such as might be found in TEXT or BLOB columns) and max_allowed_packet is too small on the source, the source fails with an error, and the replica shuts down the replication I/O thread. Row-based ...
https://dev.mysql.com/doc/refman/5.7/en/type-conversion.html
If one of the arguments is a TIMESTAMP or DATETIME column and the other argument is a constant, the constant is converted to a timestamp before the comparison is performed. If str_col is an indexed string column, the index cannot be used when ...
https://dev.mysql.com/doc/refman/5.7/en/charset-binary-collations.html
This section describes how the binary collation for binary strings compares to _bin collations for nonbinary strings. Binary strings (as stored using the BINARY, VARBINARY, and BLOB data types) have a character set and collation named binary.