MySQL Storage engine overview

MySQL tutorial is different from most database tutorials, there is a storage engine in MySQL, for different needs, users can choose the most suitable for their own storage engine, then there are many types of storage engine MySQL, and their advantages and disadvantages,

The MySQL engine has four kinds: myisam,innodb,bdb,memory,merge,example,ndb cluster,archive,csv,blackhole,federated and so on, other InnoDB, With BDB is providing a transaction security table, other storage engines are non-transactional security tables.

Here we look at the different tables of Jane.

First, MyISAM

MyISAM is the MySQL default storage engine, which does not support transaction processing and also does not support foreign keys, which has the advantage of being fast and not requiring transactional integrity.

MyISAM a datasheet, there are three table files on your hard disk that are. frm (storage table definition). MYD (Data storage table). MYI (store Index Table)

Second, InnoDB

InnoDB table automatic growth column, can be entered manually, but if the value is 0 or empty, then the actual insertion will be automatically increase the value of the InnoDB table automatic growth must be set to index, and MyISAM not required. It also supports foreign key constraints,

Third, memory

The Memery storage engine uses content stored in memory to create tables, and each memory table only actually corresponds to one hard drive file. The format is. frm,memory access speeds are faster than two, because the data is in memory and the default engine uses a hash index, but when the server shuts down, the data in the table is lost

Iv. Merge

The merge storage engine is a group of MyISAM tables that must have the same structure, the merge itself is not data, the tables of the merge type can be queried, deleted, updated, and so on, which are actually operating on the internal MyISAM, For the Merge Type table insert operation, the table is inserted through the INERT_METHOD clause, which can have 3 different values, first,last, not defined as the No table cannot insert operations on the merge.

Okay, here's a brief description of the common MySQL storage engine,

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