Skip to content

CMA Intermediate · Financial Management and Business Data Analytics · Data Processing, Organisation, Cleaning and Validation

A company keeps its sales invoices in a table where Invoice No. is unique for each row. A separate Customer table has Customer ID as its unique identifier, and the invoice table also carries Customer ID to link each invoice to a customer. In the invoice table, Customer ID is a:

Customer ID in the invoice table is a foreign key. It refers to the primary key of another table, the Customer table, and so links each invoice to its customer. The invoice table's own primary key is Invoice No.

  1. APrimary key
  2. BForeign keyCorrect
  3. CComposite key
  4. DSurrogate index

Explanation

Invoice No. uniquely identifies rows in the invoice table, so it is the primary key. Customer ID in the invoice table refers to the primary key of the Customer table, which makes it a foreign key. A composite key would need two or more fields combined to identify a row, which is not the case here.

Did you get it right without looking?

One question tells you little. A timed set on Data Processing, Organisation, Cleaning and Validation shows your real accuracy, how long you take and where you lose marks.

Practise Data Processing, Organisation, Cleaning and ValidationFree diagnostic mock

More Data Processing, Organisation, Cleaning and Validation questions