所以我有以下C#方法将DataTable上传到SQL表(Sql Server 2008)
public bool ImportData(DataTable dtImport, string _importtype, string _custno)
{
bool success = false;
string constr = System.Configuration.ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
SqlConnection con = new SqlConnection(constr);
try
{
con.Open();
if (con.State == ConnectionState.Open)
{
SqlCommand cmdProc = new SqlCommand("JR_SP_ImportDatatable", con);
cmdProc.CommandType = CommandType.StoredProcedure;
cmdProc.Parameters.AddWithValue("@Details", dtImport);
cmdProc.Parameters.AddWithValue("@Type", _importtype);
cmdProc.Parameters.AddWithValue("@Custno", _custno);
cmdProc.ExecuteNonQuery();
success = true;
}
}
catch (Exception ex)
{
string msg = "Fetch Error:";
msg += ex.Message;
throw new Exception(msg);
}
finally
{
}
return success;
}
我还创建了一个用户定义的表格类型如下......
CREATE TYPE [dbo].[ImportTable] AS TABLE(
[fname] [varchar](max) NULL,
[lname] [varchar](max) NULL,
[date1] [varchar](max) NULL,
[fname2] [varchar](max) NULL,
[lname2] [varchar](max) NULL,
[date2] [varchar](max) NULL,
[salutation] [varchar](max) NULL,
[name1] [varchar](max) NULL,
[name2] [varchar](max) NULL,
[company] [varchar](max) NULL,
[address] [varchar](max) NULL,
[address2] [varchar](max) NULL,
[city] [varchar](max) NULL,
[state] [varchar](max) NULL,
[zip] [varchar](max) NULL,
[custno] [varchar](max) NULL
)
GO
请注意,在我的Sql表中,我不允许在任何这些字段中使用NULL值,因此当它们在Datatable中为空时,默认值为(''),因此它会插入一个空值。
我的问题是它抛出错误“获取错误:无法将值NULL插入列'fname2',表'dbo.UsersMailingData';列不允许空值.INSERT失败。 声明已经终止。
但是当我调试我正在发送到存储过程的数据表时,它的列fname2具有空值。有什么理由认为它是空的吗?为了简短起见,我的fname2字段仅在我的sql表中...
[fname2] [nvarchar](max) NOT NULL
有这个约束
ALTER TABLE [dbo].[UsersMailingData] ADD CONSTRAINT [DF_UsersMailingDataFinal_fname2] DEFAULT (' ') FOR [fname2]
GO
最后,这是我用来插入记录的存储过程...
CREATE PROCEDURE [dbo].[JR_SP_ImportDatatable]
@Details ImportTable Readonly,
@Type varchar(max),
@Custno varchar(max)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
-- Insert statements for procedure here
DECLARE @rownum int
IF EXISTS(SELECT * FROM UsersMailingData WHERE custno = @Custno)
SET @rownum = (SELECT MAX(recip_id)+1 FROM UsersMailingData WHERE custno = @Custno)
ELSE
SET @rownum = 0
IF(@Type = 'Add')
BEGIN
INSERT INTO UsersMailingData(recip_id, fname, lname, date1, fname2, lname2, date2, salutation, name1, name2, company, address, address2, city, state, zip, custno)
SELECT row_number() over (order by custno)+@rownum, fname, lname, date1, fname2, lname2, date2, salutation, name1, name2, company, address, address2, city, state, zip, custno FROM @Details
OPTION (RECOMPILE);
END
IF(@Type = 'Replace')
BEGIN
DELETE FROM UsersMailingData
WHERE Custno = @Custno
INSERT INTO UsersMailingData(recip_id, fname, lname, date1, fname2, lname2, date2, salutation, name1, name2, company, address, address2, city, state, zip, custno)
SELECT row_number() over (order by custno)+@rownum, fname, lname, date1, fname2, lname2, date2, salutation, name1, name2, company, address, address2, city, state, zip, custno FROM @Details
OPTION (RECOMPILE);
END
END
GO
如果有人对我为什么会收到此错误有任何想法,那将会很有帮助。
答案 0 :(得分:2)
列默认仅适用于您未提供值的情况。以下是有区别的:
Insert TableWithThreeColumns(One,Two) values ('One','Two')
-- Third, unnamed column gets default
和
insert TableWithThreeColumns(One,Two,Tree) values ('One','Two',NULL)
-- Column will NOT get default: it will try to put in NULL
您可以在选择期间从源中测试null,而不是使用默认约束:
insert into table (column1,column2)
select isnull(column1,''),isnull(column2,'')