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https://dev.mysql.com/features.html
Data Types Many data types: signed/unsigned integers 1, 2, 3, 4, and 8 bytes long, FLOAT, DOUBLE, CHAR, VARCHAR, BINARY, VARBINARY, TEXT, BLOB, DATE, TIME, DATETIME, TIMESTAMP, YEAR, SET, ENUM, and OpenGIS spatial types. MySQL Server supports many ... This section describes some of the important characteristics of the MySQL Database ...
https://dev.mysql.com/general-thread-states.html
For the end state, the following operations could be happening: Writing an event to the binary log Freeing memory buffers, including for blobs Killed Someone has sent a KILL statement to the thread and it should abort next time it checks the kill ...
https://dev.mysql.com/innodb-buffer-pool-flushing.html
When table data is stored on a traditional HDD storage device, flushing neighbor pages in one operation reduces I/O overhead (primarily for disk seek operations) compared to flushing individual pages at different times. For table data stored on SSD, ... InnoDB performs certain tasks in the background, including flushing of dirty pages from the buffer ...
https://dev.mysql.com/innodb-cmp-table.html
COMPRESS_OPS The number of times a B-tree page of size PAGE_SIZE has been compressed. COMPRESS_OPS_OK The number of times a B-tree page of size PAGE_SIZE has been successfully compressed. COMPRESS_TIME The total time in seconds used for attempts to ... The INNODB_CMP and INNODB_CMP_RESET tables provide status information on operations related to compressed InnoDB ...
https://dev.mysql.com/insert-optimization.html
You can use the following methods to speed up inserts: If you are inserting many rows from the same client at the same time, use INSERT statements with multiple VALUES lists to insert several rows at a time. This is considerably faster (many times ... To optimize insert speed, combine many small operations into a single large ...
https://dev.mysql.com/memory-use.html
A buffer pool that is too small may cause excessive churning as pages are flushed from the buffer pool only to be required again a short time later. The memory is only allocated when needed, but it might be used if your replication topology handles ... MySQL allocates buffers and caches to improve performance of database ...
https://dev.mysql.com/myisampack.html
When the table is used later, the server reads into memory the information needed to decompress columns. This results in much better performance when accessing individual rows, because you only have to uncompress exactly one row. MySQL uses mmap() ...
https://dev.mysql.com/mysql-cluster-logs-cluster-log.html
LCPFragmentCompleted Checkpoint 11 INFO Node node_id: ACC Blocked num_1 and TUP Blocked num_2 times last second Undo logging is blocked because the log buffer is close to overflowing. Its state at the time of failure is described by an arbitration ... The following table lists the most common NDB cluster log ...
https://dev.mysql.com/mysql-cluster-ndbinfo-threadstat.html
The values of the os_ru_utime, os_ru_stime, os_ru_minflt, os_ru_majflt, os_ru_nvcsw, and os_ru_nivcsw columns are obtained using the system getrusage() call, or the equivalent. Since this table contains counts taken at a given point in time, for ...
https://dev.mysql.com/mysql-cluster-programs-ndb-index-stat.html
All NDB 8.0 releases --verbose, -v Turn on verbose output All NDB 8.0 releases --loops=# Set the number of times to perform a given command. --loops=# Property Value Command-Line Format --loops=# Type Numeric Default Value 0 Minimum Value 0 Maximum ... ndb_index_stat provides per-fragment statistical information about indexes on NDB ...
Document created the 26/06/2006, last modified the 26/10/2018
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