3. Study the result of this SELECT statement:
SQL> select * from t1; C1 C2 C3 C4--- --- --- --- 1 2 3 4 5 6 7 8If you issue this statement:
insert into t1 (c1,c2) values(select c1,c2 from t1);why will it fail? (Choose the best answer.)
A. Because values are not provided for all the table’s columns: there should
be NULLs for C3 and C4.
B. Because the subquery returns multiple rows: it requires a WHERE clause to
restrict the number of rows returned to one.
C. Because the subquery is not scalar: it should use MAX or MIN to generate
scalar values.
D. Because the VALUES keyword is not used with a subquery.
E. It will succeed, inserting two rows with NULLs for C3 and C4.
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