加上查詢條件Select A.Vits_name,C.Specialties_name
From vits A
Inner Join vet_specialties B
On A.Vits_ID=B.Vit_ID
Inner Join specialties C
On B.Specialty_ID=C.Specialties_ID
Where A.Vits_ID=條件或者Select A.Vits_name,C.Specialties_name
From vits A
Inner Join vet_specialties B
On A.Vits_ID=B.Vit_ID
Inner Join specialties C
On B.Specialty_ID=C.Specialties_ID
Where A.Vits_name=條件
From vits A
Inner Join vet_specialties B
On A.Vits_ID=B.Vit_ID
Inner Join specialties C
On B.Specialty_ID=C.Specialties_ID
Where A.Vits_ID=條件或者Select A.Vits_name,C.Specialties_name
From vits A
Inner Join vet_specialties B
On A.Vits_ID=B.Vit_ID
Inner Join specialties C
On B.Specialty_ID=C.Specialties_ID
Where A.Vits_name=條件
From vits A
left Join vet_specialties B
On A.Vits_ID=B.Vit_ID
left Join specialties C
On B.Specialty_ID=C.Specialties_ID
Where A.Vits_name=條件
用left join可以查出没有专业的兽医