Using UNICODE function or NCHAR function in SQL Server 2012

The T-SQL provides UNICODE function and NCHAR function.

First function get one argument(string expression) as nchar or nvarchar datatype and return int value. This returned value is decimal code for char in UTF-16 encoding. This function get only first char from string(argument of function). It is example for ‘a’ letter.

SELECT UNICODE('a') as [UNICODE(a)]

Result:

For diacritic chars this function works very well, either.

SELECT UNICODE('ą') as [UNICODE(ą)]

Result:

For check this values, You may use NCHAR function. This function get one argument as decimal code in UTF-16 of char. It returns nchar(1) value or nvarchar(2) value, it depends on database supplementary characters.

So let check ‘a’ and ‘ą’ letters.

 SELECT NCHAR(97) as [NCHAR(97)] , 
        NCHAR(261) as [NCHAR(261)] ;

Result:

You may see the same chars, that was be displayed in first and second example.