MYSQL按位與

Question

LanguageTable
language_ID | language
1           | english
2           | german
3           | french

EmployeeTable
employee_ID | language_ID
1           | 1
2           | 2
2           | 3
3           | 3
4           | 2

選擇會說德語和法語的員工

而且不要告訴我

從EmployeeTable中選擇EmployeeTable.employee_ID，Language_ID = 3＆2

因為那行不通

Answer 1

select a.employee_ID  from EmployeeTable a join EmployeeTable b on a.employee_ID =b.employee_ID  where a.language_ID='2' and b.language_ID='3'

嘗試這個