MYSQL按位与

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

选择会说德语和法语的员工

别告诉我

SELECT EmployeeTable.employee_ID 从EmployeeTable WHERE language_ID = 3＆2

因为那行不通

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'

尝试