单项选择题
A.Foreign key references cannot cross schema boundaries.
B.A DB2 user must be created before a schema with the same name can be created.
C.If no schema is specified when an object is created, the default schema PUBLIC is used.
D.A schema enables the creation of multiple objects in a database without encountering namespace collisions.
单项选择题 Which of the following scenarios will ensure that the value of the NEXT_STEPNO column in a given row of table TABLEX exists as a value of column STEPNO (usually in another row) in the same table?（）
单项选择题 An application needs to store a 5 MB JPEG image in a DB2 table. Which data type should be specified for the column that will be used for storing the image?（）
单项选择题 Given the following requirements: Create a table to contain employee data, with a unique numeric identifier automatically assigned when a row is added, has an EDLEVEL column that permits only the values C, H and N, and permits inserts only when a corresponding value for the employees department exists in the DEPARTMENT table. Which of the following CREATE statements will successfully create this table?（）