Which of the following is WRONG in the relation rules?
A: There is no order on the rows.
B: There is no order on the columns.
C: Two tuples cannot be identical in all column values.
D: Multi-valued attributes are permitted.
A: There is no order on the rows.
B: There is no order on the columns.
C: Two tuples cannot be identical in all column values.
D: Multi-valued attributes are permitted.
举一反三
- Which of the following is WRONG in the relation rules? A: There is no order on the rows. B: There is no order on the columns. C: Two tuples can be identical in all column values. D: Multi-valued attributes are not permitted.
- Which statement is true regarding the INTERSECT operator?（） A: It ignores NULL values B: Reversing the order of the intersected tables alters the result C: The names of columns in all SELECT statements must be identical D: The number of columns and data types must be identical for all SELECT statements in the query
- Which statement is true regarding the INTERSECT operator?（） A: It ignores NULL values B: Reversing the order of the intersected tables alters the result C: The names of columns in all SELECT statements must be identical D: The number of columns and data types must be identical for all SELECT statements in the query&e
- 中国大学MOOC: Which of the following is WRONG in the relation rules?
- Which of the following expressions is wrong in order?