Can a foreign key reference more than one table?

Question

would like to know if it is possible for a foreign key to reference more than one table, for example:

client table
PK - client code
- client name

employee table
PK - official code
- official name

contact table
- telephone
- e-mail
FK - contact code, client table reference(client code), employee table reference (employee code)

Answer 1

A foreign key cannot reference more than one table; in fact, this would go against the principles of data logic modeling itself.

The most correct way to relate the tables in the mentioned example would be:

Client table:

• PK client code

• FK contact code (reference to contact table)

• client name

Employee table:

• PK official code

• FK contact code (reference to contact table)

• official name

Table contact:

• PK contact code
• telephone
• e-mail