Performance impact of concatenating NVARCHAR with varchar and ''(single quote single quote)

Question

What is the datatype of '' in sql server and does performance hit when concatenating nvarchar, varchar, and ''.

What are the implicit conversions here?

The exact datatype depends on whether or not the string literal has the `N` prefix and the length of the string. Concatenating a string without the `N` prefix that is between 4K and 8K characters long to an nvarchar will [always cause truncation](http://stackoverflow.com/questions/12639948/sql-nvarchar-and-varchar-limits/12639972#12639972) as it gets cast to `nvarchar(4000)` — Martin Smith, Nov 14 '13 at 10:48

score 2 · Accepted Answer · answered Nov 14 '13 at 10:43

2

It is varchar. Use

select sql_variant_property('','BaseType')

answered Nov 14 '13 at 10:43

juergen d

Is there any similar function which catches nvarchar(max) too – blogbydev Nov 14 '13 at 10:52

1 Answers1