Question

    SELECT
employees.emp_id,
employees.emp_name_en,
employees.emp_name_ar,
employees.emp_nike_name,
employees.emp_basic_salary,
employees.emp_aw_food,
employees.emp_aw_car,
employees.emp_aw_mobile,
employees.emp_aw_trans,
employees.emp_aw_housing,

((`settings`.`set_value` * `employees`.`emp_basic_salary`) / 100) AS insurance_ratio,
(((((`employees`.`emp_aw_housing` + `employees`.`emp_aw_trans`) + `employees`.`emp_aw_mobile`) + `employees`.`emp_aw_car`) + `employees`.`emp_aw_food`) + `employees`.`emp_basic_salary`) - ((`settings`.`set_value` * `employees`.`emp_basic_salary`) / 100)  AS net_salary,
  (net_salary / 30 ) AS day_salary
FROM
employees ,
settings
WHERE
settings.set_key =  'insurance_ratio'

[Err] 1054 - “字段列表”中的未知列'net_salary'

我如何使用列'net_salary'

Answer 1

但你能做些什么......

SELECT tab1.*, (tab1.net_salary / 30 ) AS day_salary 
FROM (SELECT
employees.emp_id,
employees.emp_name_en,
employees.emp_name_ar,
employees.emp_nike_name,
employees.emp_basic_salary,
employees.emp_aw_food,
employees.emp_aw_car,
employees.emp_aw_mobile,
employees.emp_aw_trans,
employees.emp_aw_housing,

((`settings`.`set_value` * `employees`.`emp_basic_salary`) / 100) AS insurance_ratio,
(((((`employees`.`emp_aw_housing` + `employees`.`emp_aw_trans`) + `employees`.`emp_aw_mobile`) + `employees`.`emp_aw_car`) + `employees`.`emp_aw_food`) + `employees`.`emp_basic_salary`) - ((`settings`.`set_value` * `employees`.`emp_basic_salary`) / 100)  AS net_salary
FROM
employees ,
settings
WHERE
settings.set_key =  'insurance_ratio') AS tab1

Answer 2

是的，对于需要重复使用的大量计算列来说，这是一个众所周知的痛苦。

select emp_id,emp_name_en,emp_name_ar,emp_nike_name,emp_basic_salary,
emp_aw_food,emp_aw_car,emp_aw_mobile,emp_aw_trans,emp_aw_housing,
(net_salary / 30 ) AS day_salary
FROM
(   SELECT
    employees.emp_id,
    employees.emp_name_en,
    employees.emp_name_ar,
    employees.emp_nike_name,
    employees.emp_basic_salary,
    employees.emp_aw_food,
    employees.emp_aw_car,
    employees.emp_aw_mobile,
    employees.emp_aw_trans,
    employees.emp_aw_housing,

    ((`settings`.`set_value` * `employees`.`emp_basic_salary`) / 100) AS insurance_ratio,
    (((((`employees`.`emp_aw_housing` + `employees`.`emp_aw_trans`) + `employees`.`emp_aw_mobile`) + `employees`.`emp_aw_car`) + `employees`.`emp_aw_food`) + `employees`.`emp_basic_salary`) - ((`settings`.`set_value` * `employees`.`emp_basic_salary`) / 100)  AS net_salary
    FROM
    employees ,
    settings
    WHERE
    settings.set_key =  'insurance_ratio'
) d;

Mysql无法在查询中使用AS

2 个答案: