| InnoDB | |
|---|---|
| Developed by | Oracle Corporation |
| OS | Cross-platform |
| Genre | Database engine |
| License | GPL or proprietary |
| Website | http://www.innodb.com/ |
InnoDB is a storage engine for MySQL, included as standard in all current binaries distributed by MySQL AB. A software developer is a person or organization concerned with facets of the software development process wider than design and coding a somewhat broader scope of Oracle Corporation ( specializes in developing and marketing Enterprise software products — particularly Database management systems In 2007 Oracle ranked An operating system (commonly abbreviated OS and O/S) is the software component of a Computer system that is responsible for the management and coordination In computing cross-platform (also known as multi-platform) is a term used to refer to Computer software or computing methods and concepts that are implemented Computer software can be organized into categories based on common function type or field of use A database engine is the underlying software component that a Database management system (DBMS uses to create retrieve update and delete (see CRUD (acronym A software license (or software licence in commonwealth usage is a Legal instrument governing the usage or redistribution of copyright protected software Proprietary software is Computer software on which the producer has set restrictions on use private modification copying, or republishing. A website (alternatively web site or Web site, a back-construction from the Proper noun World Wide Web) is a collection of Web pages A database engine is the underlying software component that a Database management system (DBMS uses to create retrieve update and delete (see CRUD (acronym MySQL is a Relational database management system (RDBMS which has more than 11 million installations MySQL AB (founded 1995 acquired by Sun Microsystems 2008 was dual headquartered in Uppsala, Sweden and Cupertino, California Its main enhancement over other storage engines available for use with MySQL is ACID-compliant transaction support, similar to PostgreSQL, along with foreign key support (declarative referential integrity). In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are A database transaction is a unit of work performed against a Database management system or similar system that is treated in a coherent and reliable way independent of other PostgreSQL is an Object-relational database management system (ORDBMS
InnoDB became a product of Oracle Corporation after their acquisition of Innobase Oy, in October 2005[1]. Oracle Corporation ( specializes in developing and marketing Enterprise software products — particularly Database management systems In 2007 Oracle ranked The software is dual licensed. Dual-licensing is the practice of distributing Software under two different sets of terms and conditions It is distributed under the GNU General Public License, but can also be licensed to parties wishing to combine InnoDB in proprietary software. Proprietary software is Computer software on which the producer has set restrictions on use private modification copying, or republishing. [2]
Comparison with MyISAM
MyISAM is the usual alternative engine and the following properties are some which distinguish the two:
- InnoDB recovers from a crash or other unexpected shutdown by replaying its logs. MyISAM is the default Storage engine for the MySQL Relational database management system. MyISAM must fully scan and repair or rebuild any indexes or possibly tables which had been updated but not fully flushed to disk. Since the InnoDB approach is approximately fixed time while the MyISAM time grows with the size of the data files, InnoDB offers greater perceived availability and reliability as database sizes grow.
- MyISAM relies on the operating system for caching reads and writes to the data rows while InnoDB does this within the engine itself, combining the row caches with the index caches. Dirty (changed) database pages are not immediately sent to the operating system to be written by InnoDB, which can make it substantially faster than MyISAM in some situations.
- InnoDB stores data rows physically in primary key order while MyISAM typically stores them mostly in the order in which they are added. Storing the rows in primary key order corresponds to the MS SQL Server feature of “Clustered Indexes” and the Oracle feature known as "index organized tables. Microsoft SQL Server is a Relational database management system (RDBMS produced by Microsoft. Oracle Database (commonly referred to as Oracle RDBMS or simply Oracle) is a Relational database management system (RDBMS produced and marketed by " When the primary key is selected to match the needs of common queries this can give a substantial performance benefit. For example, customer bank records might be grouped by customer in InnoDB but by transaction date with MyISAM, so InnoDB would likely require fewer disk seeks and less RAM to retrieve and cache a customer account history. On the other hand, inserting data in orders that differ substantially from primary key (PK) order will presumably require that InnoDB do a lot of reordering of data in order to get it into PK order. This places InnoDB at a slight disadvantage in that it does not permit insertion order based table structuring.
- InnoDB currently does not provide the compression and terse row formats provided by MyISAM, so both the disk and cache RAM required may be larger. A lower overhead format is available for MySQL 5. 0, reducing overhead by about 20% and use of page compression is planned for a future version.
- When operating in fully ACID-compliant modes, InnoDB must do a flush to disk at least once per transaction, though it will combine flushes for inserts from multiple connections. For typical hard drives or arrays, this will impose a limit of about 200 update transactions per second. If you require higher transaction rates, disk controllers with write caching and battery backup will be required in order to maintain transactional integrity. InnoDB also offers several modes which reduce this effect, naturally leading to a loss of transactional integrity. MyISAM has none of this overhead, but only because it does not support transactions.
External links
Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic