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rows in set (0.00 sec) 

This difference is due to the fact that the cascading deletes are handled internally by the InnoDB  storage engine, which means that none of the changes are logged. 

## 15.20 InnoDB memcached Plugin 

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## Note 

The InnoDB memcached  plugin is deprecated as of MySQL 8.0.22; expect support for it to be removed in a future version of MySQL. 

The InnoDB memcached  plugin ( daemon_memcached ) provides an integrated memcached  daemon that automatically stores and retrieves data from InnoDB  tables, turning the MySQL server into a fast “key- value store” . Instead of formulating queries in SQL, you can use simple get , set , and incr  operations that avoid the performance overhead associated with SQL parsing and constructing a query optimization plan. You can also access the same InnoDB  tables through SQL for convenience, complex queries, bulk operations, and other strengths of traditional database software. 

This “NoSQL-style”  interface uses the memcached  API to speed up database operations, letting InnoDB handle memory caching using its buffer pool mechanism. Data modified through memcached  operations such as add , set , and incr  are stored to disk, in InnoDB  tables. The combination of memcached simplicity and InnoDB  reliability and consistency provides users with the best of both worlds, as explained in Section 15.20.1, “Benefits of the InnoDB memcached Plugin” . For an architectural overview, see Section 15.20.2, “InnoDB memcached Architecture” . 

## 15.20.1 Benefits of the InnoDB memcached Plugin 

This section outlines advantages the daemon_memcached  plugin. The combination of InnoDB  tables and memcached  offers advantages over using either by themselves. 

•Direct access to the InnoDB  storage engine avoids the parsing and planning overhead of SQL. 

•Running memcached  in the same process space as the MySQL server avoids the network overhead of passing requests back and forth. 

•Data written using the memcached  protocol is transparently written to an InnoDB  table, without going through the MySQL SQL layer. You can control frequency of writes to achieve higher raw performance when updating non-critical data. 

•Data requested through the memcached  protocol is transparently queried from an InnoDB  table, without going through the MySQL SQL layer. 

•Subsequent requests for the same data is served from the InnoDB  buffer pool. The buffer pool handles the in-memory caching. You can tune performance of data-intensive operations using InnoDB configuration options. 

•Data can be unstructured or structured, depending on the type of application. You can create a new table for data, or use existing tables. 

