Question

我必须从一个已设置的表（“ student”，“ staff'”）中获取类型，并且根据结果，我必须更新staff或student_class_attendance表，我会尝试这样做

SELECT TYPE  
CASE    WHEN TYPE = 'staff' THEN
        UPDATE  staff_attendance SET statues = 1 WHERE staff_id = (SELECT type_id FROM rfid_details WHERE rfid_no = '124' )     
WHEN TYPE = 'student' THEN
    UPDATE  student_class_attendance SET statues = 1 WHERE student_id = (SELECT type_id FROM rfid_details WHERE rfid_no = '124' )
END 
FROM rfid_details WHERE rfid_no = '124'

还有

SELECT TYPE  IF(TYPE = staff, 
UPDATE staff_attendance 
SET    statues = 1 
WHERE  staff_id = 

          SELECT type_id 
          FROM   rfid_details 
          WHERE  rfid_no = '124' ,UPDATE student_class_attendance 
SET    statues = 1 
WHERE  student_id= 

          SELECT type_id 
          FROM   rfid_details 
          WHERE  rfid_no = '124' ) FROM rfid_details WHERE rfid_no = '124'

但显示

您的SQL语法有错误；检查与您的MariaDB服务器版本相对应的手册，以在'CASE WHEN TYPE ='staff'THEN附近使用正确的语法在第2行上更新staff_attendance SET雕像= 1在哪里

以及

您的SQL语法有错误；查看与您的MariaDB服务器版本相对应的手册，以获取在'IF（type = staff，更新staff_attendance SET雕像= 1 在1号线的staff_i'

plz帮助解决此问题

Answer 1

您根本无法在select语句中进行更新。您可以尝试以下操作：

UPDATE  staff_attendance SET statues = 1 WHERE staff_id = (SELECT type_id FROM rfid_details WHERE rfid_no = '124' and type = 'staff');
UPDATE  student_class_attendance SET statues = 1 WHERE student_id = (SELECT type_id FROM rfid_details WHERE rfid_no = '124' and type = 'student');

根据条件更新表

1 个答案: