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If we have n no of columns in a table, can we add new
column in that table with not null constraint?

Question Posted / avmaske

Answers were Sorted based on User's Feedback



If we have n no of columns in a table, can we add new column in that table with not null constrain..

Answer / srinu

U r correct Chandan.But one thing,what is that is if the
table contains some data at that time syntax for adding new
column to that table with notnull constraint is....

alter table table_name add column_name datatype default
value constraint constraint_name not null;

if we want 2 know which columns have which constraints then
the syntax is

select column_name,constraint_type
from user_cons_columns
where table_name='EMP';

Is This Answer Correct ?    7 Yes 1 No

If we have n no of columns in a table, can we add new column in that table with not null constrain..

Answer / chandan kumar

If table is empty (means no records are there) then we can
add the constraint.

alter table tablename add (col_name datatype not null)

Is This Answer Correct ?    6 Yes 2 No

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