A rule of thumb for choosing indexes for a relational database includes which of the following?
A.Indexes are more useful on smaller tables.
B.Indexes are more useful for columns that do not appear frequently in the WHERE clause in queries.
C.Do not specify a unique index for the primary key of each table.
D.Be careful indexing attributes that have null values.
Answer:D
A rule of thumb for choosing indexes for a relational database includes which of the following?
A.Indexes are more useful on smaller tables. B.Indexes are more useful for columns that do not appear frequently in the WHERE clause in queries. C.Do not specify a unique index for the primary key of each table. D.Be careful indexing attributes that have null values.