NCHAR, NVARCHAR, NTEXT / NCLOB - supporting Unicode characters

As more companies deploy their database globally, their database needs to be able to handle Unicode. Unicode enables us to represent all the characters that are expressed in most of human written languages.

The following datatypes allow us to handle unicode characters.
   -  NCHAR, NVARCHAR,  NTEXT, NVARCHAR(max), NCLOB

And the following example shows how we can use these datatypes.

CREATE TABLE  unicodeDataTable
  (  text_id       number           Primary KEY,
     uni_text      nvarchar(20)

   );

INSERT INTO unicodeDataTable(text_id, uni_text) VALUES (1,  N'이동훈' );
INSERT INTO unicodeDataTable(text_id, uni_text) VALUES (2,  N'こんにちは' );

SELECT * FROM  unicodeDataTable;

   text_id       uni_text

   1               이동훈
   2               こんにちは

--------------------------------------------------------- 

NTEXT :  (SQL Server)  NText is going to be deprecated. Microsoft recommends that we use NVARCHAr(max).

NCLOB & CLOB  : (Oracle) store up to 8 to 128 terabytes of character data (11g)