1.In __________________, the number of (first-level) index entries is equal to the number of data blocks in data file.

a. primary index

b. cluster index

c. secondary index

d. multi-level index

2. The data definition language defines

a. the schema or the structure of a database

b. the set of operations in a database system

c. both a. and b.

3. The entity-relationship model is

a. DBMS dependent

b. DBM independent

c. both a. and b.

d. neither a. nor b.