Computer Science
What constraint should be applied on a table column so that NULL is not allowed in that column, but duplicate values are allowed.
Answer
To ensure that NULL values are not allowed in a table column while allowing duplicate values, we should use the NOT NULL constraint. The NOT NULL constraint ensures that every entry in the specified column must have a value (i.e., it cannot be NULL), but it allows duplicate values.
Related Questions
The code provided below is intended to swap the first and last elements of a given tuple. However, there are syntax and logical errors in the code. Rewrite it after removing all errors. Underline all the corrections made.
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