1. reliable units(recovery from failures and keep adatabase consistent).2. isolation between programs accessing a databaseconcurrently.A database transaction, must be atomic, consistent, isolated anddurable.ACID (atomicity, consistency, isolation, durability) is a set ofproperties that guarantee database transactions are processedreliably.
•Absence of transactions support.Characteristics:1. data values are stored with the low byte first.2. All numeric key values are stored with the high byte first.3. Large files (up to 63-bit file length).4. There is a limit of 232 (~4.295E+09) rows in a MyISAM table.5. The maximum number of indexes per MyISAM table is 64.6. The maximum key length is 1000 bytes.7. Internal handling of one AUTO_INCREMENT column per table issupported.
8. MyISAM supports concurrent inserts.9. You can put the data file and index file in different directories on differentphysical devices.10. BLOB and TEXT columns can be indexed.11. NULL values are allowed in indexed columns.12. MyIsam, flags: a. mysqld: indicates whether the table was closed correctly. b. myisamchk: marks tables as checked if you run it with the --update-state option. c. myisamchk --analyze stores statistics for portions of keys, as well asfor entire keys. d. myisampack can pack BLOB and VARCHAR columns.
* Transaction-safe (ACID compliant)• stores user data in clustered indexes.• supports FOREIGN KEY referential-integrity constraints.• designed for maximum performance.• large database sites requiring high performance, Example: Slashdot.org• stores more than 1TB of data and handles an average loadof 800 inserts/updates per second.• increase multi-user concurrency and performance(row-locking).
Stores all data in RAM for extremely fast access inenvironments that require quick lookups of referenceand other like data. This engine was formerly known asthe HEAP engine.
Allows a MySQL DBA or developer to logically group aseries of identical MyISAM tables and reference themas one object. Good for VLDB environments such asdata warehousing.
Provides the perfect solution for storing and retrievinglarge amounts of seldom-referencedhistorical, archived, or security audit information.
Offers the ability to link separate MySQL servers tocreate one logical database from many physical servers.Very good for distributed or data mart environments.
This clustered database engine is particularly suited forapplications that require the highest possible degree ofuptime and availability.
The CSV storage engine stores data in text files usingcomma-separated values format. You can use the CSVengine to easily exchange data between other softwareand applications that can import and export in CSVformat.
The Blackhole storage engine accepts but does notstore data and retrievals always return an empty set.The functionality can be used in distributed databasedesign where data is automatically replicated, but notstored locally.
1. Is your table is going to be inserted, deleted, and updated much much more than it is going to be selected????2. If you need full-text search?????3. If you prefer/require relational database design?????4. Is disk-space or ram an issue??????5. In Doubt?????
Islam Al-Zatary - Front End EngineerTwitter: islamzataryEmail: email@example.com
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