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

More Questions from Database Design Using Normalization

• One common design problem when designing a database from existing data is the use of a single cell in one column to store multiple values of an attribute.
• One common design problem when designing a database from existing data is the presence of missing values, called blank values, in received data.
• We use the SQL construct COLUMNS(*) to determine the number and type of columns in a table.
• We can eliminate modification anomalies with proper normalization that results in tables in BCNF.
• 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.
• We have normalized a table into BCNF if all candidate keys are determinants.
• When building a database from an existing set of tables, we still need to consider normalization principles.
• Multivalued dependencies create harmless anomalies that should be noted, but do not always need to be eliminated.
• Proper normalization eliminates duplicated data.
• 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.

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