Oracle Multi-Table query, ask a question

First, there is a contract table that corresponds to the database table Lg_bill_of_lading_detail abbreviated bold has a user table Emt_user short E

After the contract is approved, the Contract table will have a reviewer audit_user corresponding user table Useid, now to query all contracts, the auditor display name, no audit will not show

The following three pictures, respectively, are related to the left side of the connection condition username perfect display Total 10,742 article

respectively, the association condition is placed behind the left connection username not showing a total of 10,757

Get rid of association condition username Display Total 10,757 article

Originally wanted to ask questions, there can be no gold beans. Hey, let's make a record here (forget, the database is: Oracle 11g)

Oracle Multi-Table query, ask a question