What does N' stands for in a SQL script ? (the one used before characters in insert script)

Question

I generated an sql script like this,

INSERT [dbo].[TableName] ([Sno], [Name], [EmployeeId], [ProjectId], [Experience]) 
VALUES (1, N\'Dave\', N\'ESD157\', N\         


        

Answer 1

'abcd' is a literal for a [var]char string (or maybe text, but varchar(max) would be more common now) - occupying 4 bytes memory, and using whatever code-page the SQL server is configured for. N'abcd' is a literal for a n[var]char string (or maybe ntext, but nvarchar(max) would be preferable), occupying 8 bytes of memory using UTF-16. This allows for full international usage, and frankly n[var]char should probably be the default in most systems.

Answer 2

N is used to specify a unicode string.

Here's a good discussion: Why do some SQL strings have an 'N' prefix?

In your example N prefix is not required because ASCII characters (with value less than 128) map directly to unicode. However, if you wanted to insert a name that was not ASCII then the N prefix would be required.

INSERT [dbo].[TableName] ([Sno], [Name], [EmployeeId], [ProjectId], [Experience]) 
VALUES (1, N'Wāhi', 'ESD157', 'FD080', 7)

Answer 3

DECLARE

   TYPE name_salary_rt IS RECORD (

      table_names     VARCHAR2 (1000),

      counts  NUMBER

   );

VSQL varchar2(2000);

   TYPE name_salary_aat IS TABLE OF name_salary_rt

      INDEX BY PLS_INTEGER;


   l_employees   name_salary_aat;

BEGIN

   EXECUTE IMMEDIATE

      q'[select table_name ,count(*) CountF

           from all_tab_columns  where rownum<100

         group by table_name]'

      BULK COLLECT INTO l_employees;


   FOR indx IN 1 .. l_employees.COUNT

   LOOP

VSQL:=VSQL||'  select '''||l_employees (indx).table_names||''','''|| l_employees (indx).counts ||''' from dual ';

if indx<l_employees.COUNT then

VSQL:=VSQL|| ' union all ';

else

VSQL:=VSQL||';';

end if;


  --    DBMS_OUTPUT.put_line (l_employees (indx).table_names||','|| l_employees (indx).counts);

    --    DBMS_OUTPUT.put_line (l_employees (indx).countf);

   END LOOP;

DBMS_OUTPUT.put_line (VSQL);

-- execute immediate  VSQL; 

END;

Answer 4

each country has its own specific letters and symbols so a database set up for English US will not recognise the £ symbol which a English UK database would, the same goes for Spanish, French, German

Also other languages like Chinese, Japanese, Hebrew, Arabic don't use any Latin characters.

so anyone trying to enter any data not contained in the local character set will fail or suffer data corruption, if you are using varchar, so if there is even the remotest possibility that your database will need to support more than one local character set then you have to use the nationalised language character set aka unicode aka NChar, which allows the character sets nationality to be recorded with the character. providing international text support

Likewise adding the N Prefix to a string instructs the database to include the Nation code as well as the character code

Answer 5

This denotes that the subsequent string is in Unicode (the N actually stands for National language character set).

Which means that you are passing an NCHAR, NVARCHAR or NTEXT value, as opposed to CHAR, VARCHAR or TEXT.

• SOURCE

Answer 6

N is to specify that its a string type value.

[N]'tsql_string'

Is a constant string. tsql_string can be any nvarchar or varchar data type. If the N is included, the string is interpreted as nvarchar data type.