单项选择题
A.Create an MQT that selects the oldest month of data with the REFRESH IMMEDIATE option.
B.Create 12 separate tables, create a view based on all 12, drop the table with the oldest month's data then drop and re- create the view.
C.Create a range partitioned table, partitioned by month, and use the ALTER TABLE statement to detach the oldest month and attach storage for new data.
D.Create a single table, extract the data to be retained using UNLOAD with a SELECT statement, drop and re-create the table then load only the data to be retained.
单项选择题 Which of the following is true of an index used to support a UNIQUE constraint?（）
单项选择题 A view is created with the following statement:CREATE VIEW v1 AS SELECT col1, col2, col3, col4 FROM t1 WHERE col4 > 1000 WITH CHECK OPTIONWhat is the effect of the CHECK OPTION clause?（）
单项选择题 Which of the following are all valid DB2 data types?（）