dispatch_address_postcode
不是强制性的,即使它是空白的,它仍然会运行:
if (!is_null($_POST['personal_info_first_name']) &&
!is_null($_POST['personal_info_surname']) &&
!is_null($_POST['personal_info_email']) &&
!is_null($_POST['personal_info_telephone']) &&
!is_null($_POST['dispatch_address_country']) &&
!is_null($_POST['dispatch_address_first_name']) &&
!is_null($_POST['dispatch_address_surname']) &&
!is_null($_POST['dispatch_address_address']) &&
!is_null($_POST['dispatch_address_town']) &&
!is_null($_POST['dispatch_address_postcode']) &&
!is_null($_POST['dispatch_address_county']) &&
( ($_POST['payment_method'] == "Pay by credit card.") ||
(
($_POST['payment_method'] == "Pay by new credit card.") &&
!is_null($_POST['card_number']) &&
!is_null($_POST['expiration_date']) &&
!is_null($_POST['security_code'])
)
)
)
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是什么赋予了?
我想显示从左外连接返回的空值,字符串为"UnRegistered".
当值是整数或bool时,我只写:
ISNULL(ReturnedValue, 0) AS ReturnedValue
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但我怎么能做到:
ISNULL(ReturnedValue, 'UnRegistered') AS ReturnedValue
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我使用MS SQL SERVER.
以下是一个简单的查询,我正在NULL通过使其进行纠正'0':
SELECT
CASE WHEN R.P IS NULL THEN '0' ELSE R.P END AS 'RectifyNull'
FROM
RBase r
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这仍然是我返回NULL值时,我想的字符串值0的的结果,而不是NULL
我究竟做错了什么?
我正在尝试验证正在发送到我的控制器的json,并且我正在使用BindingResult方式,我能够正常验证字符串和其他所有内容.但我不知道如何检查枚举是空还是空.
我在SQL Server上执行以下查询,但出现错误:
SELECT DISTINCT t1.p_id "Id",
(TO_CHAR("sysdate", 'YYYY') + least(SIGN(("sysdate" - to_date('01-Aug-' | | TO_CHAR("sysdate", 'YYYY'), 'DD-Mon-RRRR'))), 0)) "Year"
FROM
t1,
t7,
t9
WHERE
t9.ei_id(+) = t7.e_id
AND (t7.e_student = t1.p_id)
AND (t7.e_module = t8.m_id)
AND (NVL(t9.ei_q18m06, t7.e_end) > '31-Jul-' | | (TO_CHAR("sysdate", 'YYYY') + least(SIGN(("sysdate" - to_date('01-Aug-' | | TO_CHAR("sysdate", 'YYYY'), 'DD-Mon-RRRR'))), 0) + - 5))
Error:
'nvl' is not a recognized built-in function name.
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知道如何避免这种情况吗?
有没有更好的方法来做这个或这个代码好吗?
DECLARE @Test DECIMAL(18,2) = NULL
, @Test1 DECIMAL(18,2) = '5'
SELECT ISNULL(@Test,(ISNULL(@Test1,'0')))
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谢谢,EB
我有一个查询(精简版 - 为了清晰起见,编辑添加SUM项目) -
SELECT STORENBR AS "Store",
DISPENSER AS "Model",
UPPER(TINTERSERIALNBR) AS "Serial",
SUM (CASE WHEN CLRNTSYS ='CCE' THEN GALLONS ELSE 0 END) AS "2018 CCE gallons",
SUM (CASE WHEN CLRNTSYS ='BAC' THEN GALLONS ELSE 0 END) AS "2018 BAC gallons",
SUM (CASE WHEN CLRNTSYS ='844' THEN GALLONS ELSE 0 END) AS "2018 844 gallons"
FROM table
GROUP BY STORENBR, DISPENSER, UPPER(TINTERSERIALNBR);
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工作得很好.但现在我必须在序列号字段中考虑NULL值.我试过了
SELECT STORENBR AS "Store",
DISPENSER AS "Model",
ISNULL(UPPER(TINTERSERIALNBR), "N/A") AS "Serial",
SUM (CASE WHEN CLRNTSYS ='CCE' …Run Code Online (Sandbox Code Playgroud) 我有两个下拉列表,一个是月份,另一个是年份.用户为他们想要检索的项目选择提交月份和年份.在数据库中,日期输入完整,例如.01/12/2009.下拉列表中有"All years"和"All months"选项,但是当用户选择其中任何一个时,它们都会得到null结果.非常感谢.这是我的查询:
SELECT ItemID, YEAR(Submit) AS SubmitYear, MONTH(Submit) AS SubmitMonth
FROM Items
WHERE (YEAR(Submit) LIKE ISNULL(@YearPay, ''))
AND (MONTH(Submit) LIKE ISNULL(@MonthPay, ''))
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我的参数是:
<asp:ControlParameter ControlID="DropDownList1" DefaultValue="" Name="YearPay" PropertyName="SelectedValue" />
<asp:ControlParameter ControlID="DropDownList2" DefaultValue="" Name="MonthPay" PropertyName="SelectedValue" />
我想要一个0,而不是列中的NULL.
给出以下两个表:
TABLE1
ClientID OrderCount
1 NULL
2 NULL
3 NULL
4 NULL
Table2
ClientID OrderCount
1 2
3 4
4 6
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注意:两个表中的OrderCount列都是INT数据类型.
UPDATE TABLE1
SET OrderCount = ISNULL(TABLE2.OrderCount,0)
FROM TABLE1
INNER JOIN TABLE2 ON TABLE2.ClientID = TABLE1.CLIENTID
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当我看到table1时,我看到了这个:
ClientID OrderCount
1 2
2 NULL
3 4
4 6
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所以,我心想 - "显然,我应该使用NULLIF而不是ISNULL",所以我改变了它们.结果相同.
我在这做错了什么?如何NULL在列中获得0而不是a ?
我能够分配如下变量:
if (Session["myVariable"] != null)
{
string variAble = Session["myVariable"].ToString();
}
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是否有方法检查对象是否为null,然后分配是否为空?