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https://dev.mysql.com/doc/refman/9.7/en/innodb-benefits.html
If you split up related data into different tables, you can set up foreign keys that enforce referential integrity. Inserts, updates, and deletes are optimized by an automatic mechanism called change buffering. InnoDB tables have the following ...
https://dev.mysql.com/doc/refman/9.7/en/innodb-compression-tuning-monitoring.html
To dig deeper into performance considerations for compressed tables, you can monitor compression performance at runtime using the Information Schema tables described in Example 17.1, “Using the Compression Information Schema Tables”. A large ...
https://dev.mysql.com/doc/refman/9.7/en/innodb-init-startup-configuration.html
On systems with a large amount of memory, you can improve concurrency by dividing the buffer pool into multiple buffer pool instances. If you have transactions that update, insert, or delete many rows, you might consider increasing the size of the ... The first decisions to make about InnoDB configuration involve the configuration of data files, log files, page size, and memory buffers, which should be configured before initializing ...
https://dev.mysql.com/doc/refman/9.7/en/keywords.html
Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Some keywords which are otherwise ...
https://dev.mysql.com/doc/refman/9.7/en/limit-optimization.html
If you need only a specified number of rows from a result set, use a LIMIT clause in the query, rather than fetching the whole result set and throwing away the extra data. MySQL sometimes optimizes a query that has a LIMIT row_count clause and no ...
https://dev.mysql.com/doc/refman/9.7/en/log-destinations.html
For users who have access to the .CSV files that contain log table data, the files are easy to import into other programs such as spreadsheets that can process CSV input. INSERT, DELETE, and UPDATE cannot be used on a log table. MySQL Server ...
https://dev.mysql.com/doc/refman/9.7/en/mathematical-functions.html
ABS(X) Returns the absolute value of X, or NULL if X is NULL. An implication of this is that ABS(-9223372036854775808) produces an error because the result cannot be stored in a signed BIGINT value. mysql> SELECT ABS(2); -> 2 mysql> SELECT ABS(-32); ...
https://dev.mysql.com/doc/refman/9.7/en/monitor-alter-table-performance-schema.html
WORK_ESTIMATED is calculated using a formula that takes into account all of the work that ALTER TABLE performs, and may be revised during ALTER TABLE processing. stage/innodb/alter table (insert): This stage is repeated for each index added by the ... You can monitor ALTER TABLE progress for InnoDB tables using Performance ...
https://dev.mysql.com/doc/refman/9.7/en/mysql-cluster-online-add-node-example.html
In this section we provide a detailed example illustrating how to add new NDB Cluster data nodes online, starting with an NDB Cluster having 2 data nodes in a single node group and concluding with a cluster having 4 data nodes in 2 node groups.
https://dev.mysql.com/doc/refman/9.7/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. --connect-retries Command-Line ...