Question

我有一张包含不同类型费用的表格，如保险费，学费，入场费等，所有这些栏目也接受空值。

我想用0值更新这些列的所有空值。我可以为每个列编写不同的更新查询，但由于所有列的条件和值都相同，我想学习在单个更新查询中执行此操作。

Table_Fees
securityFees | TuitionFees | AdmissionFees
 150            500             null
 null           450              120
 150            null             120

如何将所有空值替换为零？

Update Table_Fees
 set securityFees = 0,
     TuitionFees  = 0,
     AdmissionFees = 0
where securityFees = null 
and   TuitionFees  = null
and   AdmissionFees = null;

或/和这两个运算符在这种情况下都没用

PS：我无法改变表的结构。我只能通过编码将0替换为空值。

Answer 1

如果您使用MySQL

Update Table_Fees
 set securityFees = IFNULL(securityFees,0),
     TuitionFees  = IFNULL(TuitionFees,0),
     AdmissionFees = IFNULL(AdmissionFees,0)
where securityFees is null 
or   TuitionFees  is null
or   AdmissionFees is null;

Answer 2

Update Table_Fees
set securityFees = IFNULL(securityFees,0),
    TuitionFees  = IFNULL(TuitionFees,0),
    AdmissionFees = IFNULL(AdmissionFees,0)

// 3 individual querys

Update Table_Fees
set securityFees = 0
where securityFees is null;

Update Table_Fees
set TuitionFees = 0
where TuitionFees is null;

Update Table_Fees
set AdmissionFees = 0
where AdmissionFees is null;

如果必须在整个表格中更新，则无需在何处条件。

希望这适合你。

如果有任何问题，请告诉我

Answer 3

运行此命令，您将获得所需的输出描述。

SELECT 'UPDATE yourtable SET ' + name + ' = NULL WHERE ' + name + ' = '''';'
FROM syscolumns
WHERE id = object_id('yourtable')
  AND isnullable = 1;

Answer 4

我已经通过CASE解决了答案

Update Table_Fees
 set securityFees = CASE when securityFees = null then 0 else securityFees END,
     TuitionFees  = CASE when TuitionFees  = null then 0 else TuitionFees  END,
     AdmissionFees = CASE when AdmissionFees = null then 0 else AdmissionFees END;

如何使用具有相同条件的单个值更新多列的多行

4 个答案: