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CHAPTER 28 • MYSQL STORAGE ENGINES AND DATA TYPESwww.it-ebooks.infobe FEDERATED rather than MyISAM. Additionally, connection parameters must be provided, whichallows Server B to communicate with the table on Server A:CREATE TABLE products (id SMALLINT NOT NULL AUTO_INCREMENT PRIMARY KEY,sku CHAR(8) NOT NULL,name VARCHAR(35) NOT NULL,price DECIMAL(6,2)) ENGINE=FEDERATEDCONNECTION='mysql://remoteuser:secret@192.168.1.103/corporate/products';The connection string should be fairly easy to understand, but a few observations are worth making.First, the user identified by username remoteuser and password secret must reside within the mysqldatabase found on Server A. Second, because this information will be transmitted over a possiblyunsecured network to Server A, it’s possible for a third party to capture not only the authenticationvariables but also the table data. See Chapter 27 for instructions regarding how to mitigate the possibilitythat a third party could acquire this data and, on the off chance that it happens, how to limit thepotential repercussions.■ Note If you need to create multiple FEDERATED tables, there is a more streamlined approach. Consult theMySQL documentation for more information.Once created, you can access the Server A products table by accessing the products table on ServerB. Furthermore, provided the user assigned in the connection string possesses the necessary privileges,it’s also possible to add, modify, and delete data residing in this remote table.Alleviating the tedium of connection management isn’t the only purpose for FEDERATED tables.Although at present MySQL’s implementation only supports connecting to tables residing on MySQLtables, in the future it should be possible to connect to other database servers, PostgreSQL or Oracle forexample.ARCHIVEEven given the present availability of low-cost, high-volume storage, organizations such as banks,hospitals, and retailers must take special care to store often enormous amounts of data in the mostefficient way possible. Because this data typically must be maintained for long periods of time, eventhough it’s perhaps rarely accessed, it makes sense to compress it, uncompressing it only whennecessary. Catering to such purposes, the ARCHIVE storage engine was added in version 4.1.3.The ARCHIVE storage engine greatly compresses any data found in a table of this type by using thezlib compression library (www.zlib.net) and uncompresses it on the fly as records are requested. Inaddition to selecting records, it’s also possible to insert records, as might be necessary when it becomespractical to migrate aging data over to an ARCHIVE table. However, it’s not possible to delete or updateany data stored within these tables.Note that any data stored in an ARCHIVE table will not be indexed, meaning SELECT operations canbe rather inefficient. If for some reason you need to perform extended analysis on an ARCHIVE table, it534