Differentiate between primary and secondary key關於「Difference between primary key and foreign key in SAP ABAP」標籤，搜尋引擎有相關的訊息討論：
Difference between Primary Key and Foreign Key - Go Codinggocoding.org › difference-between-primary-key-and-forei...What are Primary Keys and Foreign Keys? - SAPHubwww.saphub.com › abap-tutorial › what-are-primary-keys...Primary Key Example - Key Fields and Foreign Keys - YouTu