Oracle uses such diagrams for many years.<p>This is an example: <a href="https:&#x2F;&#x2F;docs.oracle.com&#x2F;cd&#x2F;B28359_01&#x2F;server.111&#x2F;b28286&#x2F;statements_10002.htm" rel="nofollow">https:&#x2F;&#x2F;docs.oracle.com&#x2F;cd&#x2F;B28359_01&#x2F;server.111&#x2F;b28286&#x2F;state...</a>