Varchar

Varchar

A varchar or Variable Character Field is a set of character data of indeterminate length. The term varchar specifically refers to a data type of a field (or column) in a database management system. Varchar fields can be of any size up to the limit. The limit differs from types of databases, an Oracle 9i Database has a limit of 4000 bytes, a MySQL Database has a limit of 65,535 bytes and Microsoft SQL Server 2005 8000 bytes (unless varchar(max) is used, which has a maximum storage capacity of 2,147,483,648 bytes).

varchar data types are popular amongst all database management systems (DBMS). This is mostly because, unlike the fixed-size char data-type, varchar does not store any blank characters, reducing the size of a database when the full length of the field is not used.

References

* [http://msdn.microsoft.com/en-us/library/ms176089.aspx CHAR and VARCHAR documentation] for Microsoft SQL Server 2008.
* [http://db.apache.org/derby/docs/dev/ref/ VARCHAR documentation] for Apache Derby.
* [http://dev.mysql.com/doc/refman/5.1/en/char.html CHAR and VARCHAR documentation] for [http://dev.mysql.com/ MySQL 5.1] .
* [http://publib.boulder.ibm.com/infocenter/idshelp/v10/index.jsp?topic=/com.ibm.sqls.doc/sqls984.htm CHAR and VARCHAR documentation] for IBM_Informix.


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