https://dev.mysql.com/host-cache-table.html
HOST The resolved DNS host name for that client IP, or NULL if the name is unknown. The host_cache table provides access to the contents of the host cache, which contains client host name and IP address information and is used to avoid Domain Name ...
https://dev.mysql.com/hosts-table.html
This is NULL for an internal thread, or for a user session that failed to authenticate. The hosts table contains a row for each host from which clients have connected to the MySQL server. For each host name, the table counts the current and total ...
https://dev.mysql.com/index-btree-hash.html
A search using col_name IS NULL employs indexes if col_name is indexed. Understanding the B-tree and hash data structures can help predict how different queries perform on different storage engines that use these data structures in their indexes, ...
https://dev.mysql.com/innodb-buffer-page-lru-table.html
The INNODB_BUFFER_PAGE_LRU table provides information about the pages in the InnoDB buffer pool; in particular, how they are ordered in the LRU list that determines which pages to evict from the buffer pool when it becomes full. The ...
https://dev.mysql.com/innodb-compression-tuning.html
Most often, the internal optimizations described in InnoDB Data Storage and Compression ensure that the system runs well with compressed data. However, because the efficiency of compression depends on the nature of your data, you can make decisions ...
https://dev.mysql.com/innodb-ft-index-cache-table.html
The INNODB_FT_INDEX_CACHE table provides token information about newly inserted rows in a FULLTEXT index. Before querying it, set the value of the innodb_ft_aux_table system variable to the name (including the database name) of the table that ...
https://dev.mysql.com/innodb-ft-index-table-table.html
The INNODB_FT_INDEX_TABLE table provides information about the inverted index used to process text searches against the FULLTEXT index of an InnoDB table. Before querying it, set the value of the innodb_ft_aux_table system variable to the name ...
https://dev.mysql.com/innodb-information-schema-fulltext_index-tables.html
INNODB_FT_BEING_DELETED: Provides a snapshot of the INNODB_FT_DELETED table; it is used only during an OPTIMIZE TABLE maintenance operation. When OPTIMIZE TABLE is run, the INNODB_FT_BEING_DELETED table is emptied, and DOC_ID values are removed from ...
https://dev.mysql.com/innodb-locking.html
Shared and Exclusive Locks Intention Locks Record Locks Gap Locks Next-Key Locks Insert Intention Locks AUTO-INC Locks Predicate Locks for Spatial Indexes InnoDB implements standard row-level locking where there are two types of locks, shared (S) ...
https://dev.mysql.com/innodb-online-ddl-failure-conditions.html
For example, you might insert duplicate values into a column while a unique index is being created, or you might insert NULL values into a column while creating a primary key index on that column. The failure of an online DDL operation is typically ...
