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What are the pre-requisites to modify datatype of a column and to add a column with NOT NULL constraint?
PL/SQL Interview Questions and Answers
(Continued from previous question...)
What are the pre-requisites to modify datatype of a column and to add a column with NOT NULL constraint?
- To modify the datatype of a column the column must be empty.
- To add a column with NOT NULL constrain, the table must be empty.
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