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MANAGING DATABASE TABLES


Table Properties 


         The heart of any database is the tables, because the tables contain the data that is used to provide information to the end users.  Tables are contained in databases, and in MySQL each database has an associated "data directory" to store all the physical components of the database, to include tables.  This physical representation on disk of the tables  is dependent on the type of storage engine that the table is utilizing; however, every table, no matter of the type of storage engine that is being used, contains a format file (table_name.frm) which describes the table definition and structure. 


            In addition to the physical representation of the table, there is also the better known logical aspect of the table. This logical aspect is represented in rows and columns.  Rows within a table, consist of a collection of values that describe an entity (ex. an employee).  Columns within a table, consist of a collection of similar data among rows (ex. employee surnames).  The intersection of row and column contains individual data items called values.  Values are always atomic, in that each position in a table may contain only one datum (piece of data). 








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