A TEXT  column with a maximum length of 65,535 (2$^{16}$ − 1) characters. The effective maximum length is less if the value contains multibyte characters. Each TEXT  value is stored using a 2-byte length prefix that indicates the number of bytes in the value. 

An optional length M  can be given for this type. If this is done, MySQL creates the column as the smallest TEXT  type large enough to hold values M  characters long. 

• MEDIUMBLOB 

A BLOB  column with a maximum length of 16,777,215 (2$^{24}$ − 1) bytes. Each MEDIUMBLOB  value is stored using a 3-byte length prefix that indicates the number of bytes in the value. 

• MEDIUMTEXT [CHARACTER SET charset_name ] [COLLATE collation_name ] 

A TEXT  column with a maximum length of 16,777,215 (2$^{24}$ − 1) characters. The effective maximum length is less if the value contains multibyte characters. Each MEDIUMTEXT  value is stored using a 3- byte length prefix that indicates the number of bytes in the value. 

• LONGBLOB 

A BLOB  column with a maximum length of 4,294,967,295 or 4GB (2$^{32}$ − 1) bytes. The effective maximum length of LONGBLOB  columns depends on the configured maximum packet size in the client/server protocol and available memory. Each LONGBLOB  value is stored using a 4-byte length prefix that indicates the number of bytes in the value. 

• LONGTEXT [CHARACTER SET charset_name ] [COLLATE collation_name ] 

A TEXT  column with a maximum length of 4,294,967,295 or 4GB (2$^{32}$ − 1) characters. The effective maximum length is less if the value contains multibyte characters. The effective maximum length of LONGTEXT  columns also depends on the configured maximum packet size in the client/server protocol and available memory. Each LONGTEXT  value is stored using a 4-byte length prefix that indicates the number of bytes in the value. 

• ENUM(’ value1 ’,’ value2 ’,...) [CHARACTER SET charset_name ] [COLLATE collation_name ] 

An enumeration. A string object that can have only one value, chosen from the list of values ’ value1 ’ , ’ value2 ’ , ... , NULL  or the special ’’  error value. ENUM  values are represented internally as integers. 

An ENUM  column can have a maximum of 65,535 distinct elements. 

The maximum supported length of an individual ENUM  element is M  <= 255 and ( M  x w ) <= 1020, where M  is the element literal length and w  is the number of bytes required for the maximum-length character in the character set. 

• SET(’ value1 ’,’ value2 ’,...) [CHARACTER SET charset_name ] [COLLATE collation_name ] 

A set. A string object that can have zero or more values, each of which must be chosen from the list of values ’ value1 ’ , ’ value2 ’ , ... SET  values are represented internally as integers. 

A SET  column can have a maximum of 64 distinct members. 

The maximum supported length of an individual SET  element is M  <= 255 and ( M  x w ) <= 1020, where M is the element literal length and w  is the number of bytes required for the maximum-length character in the character set. 

