Multiple choice technology databases

what is the len of @c? declare @c varchar(8000) set @c = N'hello' + replicate('-',8000) print len(@c) print @c

  1. 8000

  2. 4000

  3. 4005

  4. 5
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The unicode prefix N'hello' makes the string a unicode string (nvarchar), while replicate('-', 8000) produces a regular varchar string. When concatenating unicode and non-unicode strings, SQL Server implicitly converts to unicode (nvarchar), but the variable @c is declared as varchar(8000), not nvarchar. The implicit conversion truncates to 4000 characters because unicode strings require 2 bytes per character. Therefore, len(@c) returns 4000, not 8000.

AI explanation

To determine the length of the variable @c, we need to understand how the LEN() function works in SQL.

In SQL, the LEN() function is used to return the number of characters in a string. It counts the number of characters, including spaces and special characters.

In the given code snippet, the variable @c is declared as a varchar(8000). This means it can hold a maximum of 8000 characters.

The code then sets the value of @c to N'hello' + replicate('-',8000). Here, replicate('-',8000) is used to repeat the dash symbol "-" 8000 times. The resulting string is concatenated with the string "hello".

Since the LEN() function counts the number of characters in a string, it will count all the characters in @c, including the "hello" string and the repeated dashes.

Therefore, the length of @c will be the sum of the length of "hello" (5 characters) and the length of the repeated dashes (8000 characters).

So the correct answer is:

B. 4000

Keep practicing — related questions