Multiple choice technology databases

select trim(column_name1),left(column_name2,5),substring(column_name3,2,4) from Table1 - The result of the above statement is

  1. Blank removed Column_name1, first 5 character of column_name2,2 to 4 character part of string from Column_name3

  2. Blank removed Column_name1, last 5 character of column_name2,2 to 4 character part of string from Column_name3

  3. Blank removed Column_name1, first 5 character of column_name2 and 2,3,4,5 character part of string from Column_name3

  4. None of the above

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The TRIM function removes leading and trailing blanks from column_name1. LEFT(column_name2,5) returns the first 5 characters from the left side. SUBSTRING(column_name3,2,4) extracts 4 characters starting from position 2, which gives characters at positions 2, 3, 4, and 5. Option A incorrectly states '2 to 4 character part' when it should be 4 characters starting from position 2.

AI explanation

Evaluate each function against standard SQL string semantics. TRIM(column_name1) strips leading/trailing blanks. LEFT(column_name2,5) returns the FIRST 5 characters. SUBSTRING(column_name3,2,4) uses the form SUBSTRING(string, start, length): it extracts 4 characters beginning at position 2, i.e. characters at positions 2, 3, 4 and 5. Matching the options: A describes the substring as '2 to 4' (only positions 2,3,4) which is wrong; B says 'last 5 characters' for LEFT which is wrong; C says 'Blank removed column1, first 5 characters of column2, and the 2,3,4,5 character part of column3' — all three clauses are exactly correct. Therefore option C is the right answer, not 'None of the above'.