Which of the following statements correctly defines a column email that cannot be NULL?

easy📝 Conceptual Q2 of 15

SQL - Table Constraints

Which of the following statements correctly defines a column email that cannot be NULL?

A<code>email VARCHAR(100) NULL</code>

B<code>email VARCHAR(100) NOT NULL</code>

C<code>email VARCHAR(100) DEFAULT NULL</code>

D<code>email VARCHAR(100) ALLOW NULL</code>

Step-by-Step Solution

Solution:

Step 1: Identify the syntax for NOT NULL
The correct syntax to prevent NULLs is adding NOT NULL after the data type.
Step 2: Check each option
Only email VARCHAR(100) NOT NULL uses NOT NULL correctly; others allow NULL or use invalid keywords.
Final Answer:
email VARCHAR(100) NOT NULL -> Option B
Quick Check:
Correct syntax for NOT NULL is NOT NULL [OK]

Quick Trick: Use NOT NULL keyword after data type [OK]

Common Mistakes:

MISTAKES

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