Table extension functionality allows sharing fields with a parent table. Administrators and developers extend tables during table creation.

Typically, tables are extended to create a set of records that share information with each other.

In the use case listed below, the Task table has multiple extensions:

A table extending another table is called a child table, and a table extended by it is called a parent table. A table can be both a parent and a child at the same time.

Table extending causes the following:

• Cross-table linking between from the new table to the extending one;
• System fields are created in the new table (like the sys_id field).

Instance administrators can use these tools to understand the relationships between the tables:

• Tables list (navigate to System Definition → All Tables).