TEXT vs. VARCHAR
Posted by Sheeri Cabral on Jan 20, 2010
On first glance, it looks like TEXT and VARCHAR can store the same information. However, there are fundamental differences between the way TEXT fields and VARCHAR fields work, which are important to take into consideration.
Standard
VARCHAR is actually part of the ISO SQL:2003 standard; The TEXT data types, including TINYTEXT, are non-standard.
Storage
TEXT data types are stored as separate objects from the tables and result sets that contain them. This storage is transparent — there is no difference in how a query involving a TEXT field is written versus one involving a VARCHAR field. Since TEXT is not stored as part of a row, retrieval of TEXT fields requires extra [edited 1/22] memory overhead.
