Explore topic-wise MCQs in Engineering.

One common design problem when designing a database from existing data is the use of a general-purpose remarks column in the received data.

One common design problem when designing a database from existing data is the presence of missing values, called blank values, in received data.

Normalization requires programmers to write more complex SQL.

One common design problem when designing a database from existing data is the presence of inconsistent values in the received data.

When building a database from an existing set of tables, we may safely assume that there are no multivalued dependencies in the data we are given.

The design guidelines and priorities for read-only databases are different because read-only databases are never updated.

We use the SQL construct COUNT(*) to count the number of rows in a table.

When you are given a set of tables and asked to create a database to store their data, the first step is to create the new database.

Each index consumes extra storage space and also requires overhead maintenance time whenever indexed data change value.

The phrase "SALE.CNumber must exist in CUSTOMER.CNumber" is a referential integrity constraint.

Indexes can usually be created for both primary and secondary keys.

The HAVING clause acts like a WHERE clause, but it identifies groups that meet a criterion, rather than rows.

SQL is a data sublanguage.

The qualifier DISTINCT must be used in an SQL statement when we want to eliminate duplicate rows.

The result of every SQL query is a table.

COUNT(field_name) tallies only those rows that contain a value; it ignores all null values.

SUM, AVG, MIN, and MAX can only be used with numeric columns.

When building a database from an existing set of tables, we may safely assume that referential integrity constraints have been enforced on the data we are given.

Most of the time, modification anomalies cause problems that are severe enough that a table should be normalized into BCNF.

When building a database from an existing set of tables, we still need to consider normalization principles.

We have normalized a table into BCNF if all candidate keys are determinants.

The condition in a WHERE clause can refer to only one value.

We use the SQL construct COLUMNS(*) to determine the number and type of columns in a table.

The ADD command is used to enter one row of data or to add multiple rows as a result of a query.

SQL provides the AS keyword, which can be used to assign meaningful column names to the results of queries using the SQL built-in functions.

The SELECT command, with its various clauses, allows users to query the data contained in the tables and ask many different questions or ad hoc queries.

A SELECT statement within another SELECT statement and enclosed in square brackets ([...]) is called a subquery.

The SQL keyword(s) ________ is used with wildcards.

A subquery in an SQL SELECT statement is enclosed in:

To remove duplicate rows from the results of an SQL SELECT statement, the ________ qualifier specified must be included.

SQL query and modification commands make up a(n) ________ .

Multivalued dependencies should ________ be eliminated.

Multivalued dependencies create harmless anomalies that should be noted, but do not always need to be eliminated.