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https://dev.mysql.com/doc/refman/8.4/en/innodb-file-defragmenting.html
One symptom of fragmentation is that a table takes more space than it “should” take. Another symptom of fragmentation is that a table scan such as this takes more time than it “should” take: SELECT COUNT(*) FROM t WHERE non_indexed_column <> ... Random insertions into or deletions from a secondary index can cause the index to become ...
https://dev.mysql.com/doc/heatwave/en/mys-hw-secondary-load.html
You can load tables into HeatWave using the SECONDARY_LOAD clause. Loading Tables Statement To load a table into MySQL HeatWave, specify the SECONDARY_LOAD clause in an ALTER TABLE statement and use the following syntax. ALTER TABLE table_name ...
https://dev.mysql.com/doc/refman/8.4/en/federated-create-server.html
If you are creating a number of FEDERATED tables on the same server, or if you want to simplify the process of creating FEDERATED tables, you can use the CREATE SERVER statement to define the server connection parameters, just as you would with the ...For more information on CREATE SERVER, see Section 15.1.18, “CREATE SERVER ...
https://dev.mysql.com/doc/refman/8.4/en/static-format.html
It is used when the table contains no variable-length columns (VARCHAR, VARBINARY, BLOB, or TEXT). Also, when scanning a table, it is very easy to read a constant number of rows with each disk read operation. MyISAM table indexes can always be ...Of ...
https://dev.mysql.com/doc/refman/8.4/en/create-table-secondary-indexes.html
Even with additional write costs, secondary indexes on virtual columns may be preferable to generated stored columns, which are materialized in the clustered index, resulting in larger tables that require more disk space and memory. row ...A ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-server-locks.html
The server_locks table is similar in structure to the cluster_locks table, and provides a subset of the information found in the latter table, but which is specific to the SQL node (MySQL server) where it resides. (The cluster_locks table provides ...This may be useful for correlating locking patterns with specific MySQL user sessions, queries, or use ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-transporters.html
Notes For each running data node in the cluster, the transporters table displays a row showing the status of each of that node's connections with all nodes in the cluster, including itself. This information is shown in the table's status column, ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-select-all.html
ndb_select_all prints all rows from an NDB table to stdout. Usage ndb_select_all -c connection_string tbl_name -d db_name [> file_name] Options that can be used with ndb_select_all are shown in the following table. --database=dbname, -d dbname Name ...--connect-retries Command-Line Format --connect-retries=# Type Integer Default Value 12 Minimum Value 0 Maximum Value 12 Number of times to retry connection before giving ...
https://dev.mysql.com/doc/refman/8.4/en/reproducible-test-case.html
For information about steps to take when encountering InnoDB table corruption, see Section 1.6, “How to Report Bugs or Problems”. If you encounter corrupted MyISAM tables or if mysqld always fails after some update statements, you can test ...
https://dev.mysql.com/doc/refman/8.4/en/sys-innodb-buffer-stats-by-table.html
These views summarize the information in the INFORMATION_SCHEMA INNODB_BUFFER_PAGE table, grouped by schema and table. Warning Querying views that access the INNODB_BUFFER_PAGE table can affect performance. Do not query these views on a production ...To avoid impacting performance on a production system, reproduce the issue you want to investigate and query buffer pool statistics on a test ...