https://dev.mysql.com/rewriter-query-rewrite-plugin-reference.html
Users communicate with the plugin by modifying the set of rules stored in this table. The plugin communicates information to users by setting the table's message column. Note The rules table is loaded into the plugin by the flush_rewrite_rules ...
https://dev.mysql.com/selecting-columns.html
If you do not want to see entire rows from your table, just name the columns in which you are interested, separated by commas.
https://dev.mysql.com/show-index.html
row *************************** Table: city Non_unique: 0 Key_name: PRIMARY Seq_in_index: 1 Column_name: ID Collation: A Cardinality: 4188 Sub_part: NULL Packed: NULL Null: Index_type: BTREE Comment: Index_comment: Visible: YES Expression: NULL ...
https://dev.mysql.com/slave-logs-status.html
A replication slave server creates two slave status logs in the form of InnoDB tables in the mysql system schema: the master info log slave_master_info, and the relay log info log slave_relay_log_info. The two slave status logs contain information ...
https://dev.mysql.com/socket-instances-table.html
The socket_instances table provides a real-time snapshot of the active connections to the MySQL server. The table contains one row per TCP/IP or Unix socket file connection. Information available in this table provides a real-time snapshot of the ...
https://dev.mysql.com/spatial-function-argument-handling.html
This provides additional flexibility to users because it is unnecessary to be concerned about the uniqueness of geometry data. Spatial values, or geometries, have the properties described at Section 11.4.2.2, “Geometry Class”. Specific ...
https://dev.mysql.com/statement-histogram-summary-tables.html
The statement histogram summary tables have these indexes: events_statements_histogram_by_digest: Unique index on (SCHEMA_NAME, DIGEST, BUCKET_NUMBER) events_statements_histogram_global: Primary key on (BUCKET_NUMBER) TRUNCATE TABLE is permitted for ... The Performance Schema maintains statement event summary tables that contain information about minimum, maximum, and average statement latency (see Section 26.12.17.3, “Statement Summary ...
https://dev.mysql.com/statistics-table.html
NON_UNIQUE 0 if the index cannot contain duplicates, 1 if it can. CARDINALITY An estimate of the number of unique values in the index. The information_schema_stats_expiry system variable defines the period of time before cached table statistics ...
https://dev.mysql.com/subquery-materialization.html
The index contains unique values to eliminate duplicates and make the table smaller. The optimizer uses materialization to enable more efficient subquery processing. Materialization speeds up query execution by generating a subquery result as a ...
https://dev.mysql.com/table-cache.html
Also take into account that the MyISAM storage engine needs two file descriptors for each unique open table. When you execute a mysqladmin status command, you should see something like this: Uptime: 426 Running threads: 1 Questions: 11082 Reloads: ...
