What type of MySQL column will be returned as System.Guid in C #

Question

Possible duplicate:
How to store GUID in MySQL tables?

VARCHAR will return as string
BLOB will return as byte[]
but what type of MySQL column will return as System.Guid in C #
thanks.

Edited: I found the answer

thanks to DaveHogan, which gives me the key to ORM (object binding mapping)
I started looking for information about the conversion (mapping) of the data type created by Connector / NET. I am using MySQL Dot Net Connector (Connector / NET)
There are 3 different situations that Connector / NET performs.


Below I found:

1st situation:
Start with Connnector / NET 6.1.1, CHAR (36) will be automatically converted as System.GUID to C #, and BINARY (16) will be considered as a system. Byte [].


The second situation:
If you use the old Connector / NET, BINARY (16) will be automatically converted as System.GUID when the value is passed in C #, and CHAR (36) will be considered as System.String.


3rd situation:
If you are using the new Connector / NET (newer than 6.1.1), and if you want to use BINARY (16) AS System.GUID (this is not the case by default), you need to add the option Old Guids = true connection in the connection string.
Example:

  server = localhost; user = root; password = qwerty; database = test; old guids = true; 

CHAR (36) will be converted as System.String and BINARY (16) = System.GUID

More about connection options Old guides :
MySQL 5.6 Reference Guide: 21.2.6. Connector / Network Connection String Options


-------------------------------------------------- --------------------
Additional Information:
How to insert System.GUID into MySql database
-------------------------------------------------- --------------------
This is an example table that we are going to insert into System.GUID:

  CREATE TABLE `testdata` (
   `id` int (10) unsigned NOT NULL AUTO_INCREMENT,
   `binary` binary (16) DEFAULT NULL,
   `char` char (36) DEFAULT NULL,
   PRIMARY KEY (`id`)
 ) ENGINE = InnoDB AUTO_INCREMENT = 1 DEFAULT CHARSET = utf8

Insert System.GUID into MySQL

  string constr = "server = localhost; user = root; pwd = qwerty; database = test;"
 using (MySqlConnection conn = new MySqlConnection (constr))
 {
     conn.Open ();

     // Create a System.GUID
     byte [] ba = new byte [16];
     Random rd = new Random ();
     rd.NextBytes (ba);
     System.Guid guid = new Guid (ba);

     // Prepare GUID values ​​in SQL format
     string guidForChar36 = guid.ToString ();
     string hexstring = BitConverter.ToString (guid.ToByteArray ());
     string guidForBinary16 = "0x" + hexstring.Replace ("-", string.Empty);

     string sql = "insert into testdata (` binary`, `char`)"
                + "values ​​(" + guidForBinary16 + ","
                + "'" + guidForChar36 + "');";

     MySqlCommand cmd = new MySqlCommand (sql, conn);
     cmd.ExecuteNonQuery ();

     conn.Close ();
 } 

Answer 1

EDIT:

Sorry, I misunderstood your question. You have to use

 BINARY(16) 

How you applied this to System.Guid depends on whether you use ORM, etc.

Answer 2

You can use guid as a CHAR(16) binary if you want to make the best use of storage space. or use char(36)