MySQL :: MySQL 8.0 Reference Manual

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https://dev.mysql.com/doc/refman/8.0/en/key-space.html

You can roughly calculate the size for the index file as (key_length+4)/0.67, summed over all keys. This is for the worst case when all keys are inserted in sorted order and the table doesn't have any compressed keys. If the first index part is a ...

10.12.3.1 How MySQL Uses Memory

https://dev.mysql.com/doc/refman/8.0/en/memory-use.html

InnoDB uses this variable-size buffering capability to take advantage of row prefetching, and to reduce the overhead of latching and B-tree navigation. MySQL allocates buffers and caches to improve performance of database operations. The default ...

10.10.2.3 Midpoint Insertion Strategy

https://dev.mysql.com/doc/refman/8.0/en/midpoint-insertion.html

The midpoint insertion strategy helps to improve performance when execution of a query that requires an index scan effectively pushes out of the cache all the index blocks corresponding to valuable high-level B-tree nodes. By default, the key cache ...

10.10.2.2 Multiple Key Caches

https://dev.mysql.com/doc/refman/8.0/en/multiple-key-caches.html

For an index assigned to the hot cache, if there are no queries requiring an index scan, there is a high probability that the index blocks corresponding to nonleaf nodes of the index B-tree remain in the cache. Note As of MySQL 8.0, the ...

9.6.2 How to Check MyISAM Tables for Errors

https://dev.mysql.com/doc/refman/8.0/en/myisam-check.html

It calculates a checksum for all key values in the rows and verifies that the checksum matches the checksum for the keys in the index tree. To check a MyISAM table, use the following commands: myisamchk tbl_name This finds 99.99% of all errors.

Chapter 2 Installing MySQL

https://dev.mysql.com/doc/refman/8.0/en/installing.html

To install MySQL from a source distribution or from the current development source tree, use the instructions in Section 2.8, “Installing MySQL from Source”. A summary of the procedure follows and later sections provide the details. If you plan ...

9.6.4 MyISAM Table Optimization

https://dev.mysql.com/doc/refman/8.0/en/myisam-optimization.html

OPTIMIZE TABLE does a table repair and a key analysis, and also sorts the index tree so that key lookups are faster. To coalesce fragmented rows and eliminate wasted space that results from deleting or updating rows, run myisamchk in recovery mode: ...

18.2.1 MyISAM Startup Options

https://dev.mysql.com/doc/refman/8.0/en/myisam-start.html

bulk_insert_buffer_size The size of the tree cache used in bulk insert optimization. The following options to mysqld can be used to change the behavior of MyISAM tables. Note This is a limit per thread! delay_key_write=ALL Don't flush key buffers ...

10.2.5.1 Optimizing INSERT Statements

https://dev.mysql.com/doc/refman/8.0/en/insert-optimization.html

The size of the table slows down the insertion of indexes by log N, assuming B-tree indexes. To optimize insert speed, combine many small operations into a single large operation. Ideally, you make a single connection, send the data for many new ...

15.7.3.4 OPTIMIZE TABLE Statement

https://dev.mysql.com/doc/refman/8.0/en/optimize-table.html

OPTIMIZE TABLE does not sort R-tree indexes, such as spatial indexes on POINT columns. OPTIMIZE TABLE reorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the ...

Displaying 71 to 80 of 88 total results