Resolved: Confusion regarding Question 4.
If Column is Unique then why more than 1 null value is allowed in that column?
2 answers ( 2 marked as helpful)
Hi Fahad!
Thanks for reaching out.
In SQL, a column defined as `UNIQUE` can still have more than one `NULL` value because `NULL` represents an unknown or undefined value. SQL standards specify that `NULL` values are not considered equal to each other, so each `NULL` entry is treated as a unique occurrence, allowing multiple `NULL`s in a column defined as `UNIQUE`.
Hope this helps.
Best,
Tsvetelin
Got it. Thanks
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