更新字段时违反UNIQUE KEY约束条件

Question

我正在使用gridview我添加文本框的行并添加成功完成的数据..但是，当我更新字段的电子邮件它显示错误。违反同时更新场

function: Update_U_Anonymoususerdetails 

int InsId=0, UserId=0,UserInstLink=0,UserCreditRecord=0; 
       SqlConnection Cn = new SqlConnection(Conn); 
       Cn.Open(); 
       for (int i = 0; i < GridView1.Rows.Count; i++) 
       { 
        Label Id = GridView1.Rows[i].FindControl("lblId") as Label; 
        TextBox Name = GridView1.Rows[i].FindControl("txtName") as TextBox; 
        TextBox MName = GridView1.Rows[i].FindControl("txtMName") as TextBox; 
        TextBox LName = GridView1.Rows[i].FindControl("txtLName") as TextBox; 
        TextBox Degree = GridView1.Rows[i].FindControl("txtDegree") as TextBox; 
        TextBox Title = GridView1.Rows[i].FindControl("txtTitle") as TextBox; 
        TextBox Email = GridView1.Rows[i].FindControl("txtEmail") as TextBox; 
        TextBox Institution = GridView1.Rows[i].FindControl("txtInstitution") as TextBox; 
        if (Name.Text.Trim() != null && Name.Text.Trim() !="") 
        { 
         int AId = 0; 
         if (Id != null) 
          AId = Convert.ToInt32(Id.Text); 
         else 
          AId = 0;      
         SqlCommand Cmd = new SqlCommand("UpdateOtherAuthors", Cn); 
         Cmd.CommandType = CommandType.StoredProcedure; 
         SqlParameter InID = new SqlParameter("@uiID", SqlDbType.Int);      
         InID.Direction = ParameterDirection.Output; 
         Cmd.Parameters.Add(InID); 
         Cmd.Parameters.AddWithValue("@Name", Name.Text); 
         Cmd.Parameters.AddWithValue("@MName", MName.Text); 
         Cmd.Parameters.AddWithValue("@LName", LName.Text); 
         Cmd.Parameters.AddWithValue("@Degree", Degree.Text); 
         Cmd.Parameters.AddWithValue("@Title", Title.Text); 
         Cmd.Parameters.AddWithValue("@Email", Email.Text); 
         Cmd.Parameters.AddWithValue("@Institution", Institution.Text); 
         Cmd.Parameters.AddWithValue("@Id", AId); 
         Cmd.Parameters.AddWithValue("@CaseId", CaseId);       
         Cmd.ExecuteNonQuery(); 
         UserId = int.Parse(Cmd.Parameters["@uiID"].Value.ToString());//getting error in this line first 

        } 
        if (Institution.Text.Trim() != null && Institution.Text.Trim() != "") 
        { 

         SqlCommand cmd = new SqlCommand("AddInstitution", Cn); 
         cmd.CommandType = CommandType.StoredProcedure; 
         SqlParameter oParam = new SqlParameter("@Institution", Institution.Text.ToString()); 
         SqlParameter InID = new SqlParameter("@InID",SqlDbType.Int); 
         oParam.Direction = ParameterDirection.Input; 
         InID.Direction = ParameterDirection.Output; 
         cmd.Parameters.Add(oParam); 
         cmd.Parameters.Add(InID); 
         cmd.ExecuteNonQuery(); 
         InsId = int.Parse(cmd.Parameters["@InID"].Value.ToString()); 

        } 
        UserInstLink= UserInstutionLink(UserId, InsId);// I am getting the error in this line 
        UserCreditRecord = UserCreditRecordID(UserInstLink, Name.Text, MName.Text, LName.Text, Degree.Text, Title.Text); 
        AssignContentManagementPrivileges(UserId,CaseId); 
        CreateCaseCredits(InsId, CaseId, UserCreditRecord); 

       } 
       Cn.Close(); 


store procedure i am using 

CREATE PROCEDURE [dbo].[UpdateOtherAuthors] 

(
@Name nvarchar(50), 
@MName nvarchar(50), 
@LName nvarchar(50), 
@Degree nvarchar(50), 
@Title nvarchar(50), 
@Email nvarchar(50), 
@Institution nvarchar(50), 
@Id int, 
@CaseId int, 
@uiID int output 

) 

AS BEGIN 
Declare @SameId nvarchar(50) 
if(@Id='0') 
begin 
INSERT INTO tbl_AuthorDetails VALUES(@Name,@Degree,@Title,@Email,@Institution,@CaseId,@LName,@MName) 
    Select @Id=COUNT(Email) from [User] where Email=@Email 
    if(@Id=0) 
    begin 
    exec CreateOtherAuthorsAccount @Name,@LName,@MName,@Degree,@Email 
    end 
end 
else 
begin 

set @SameId=(Select (Email) from tbl_AuthorDetails where Id=@Id) 
if(@SameId = @Email) 
    Update tbl_AuthorDetails set Name=@Name,Degree=@Degree,Title=@Title,Email=@Email,Institution=@Institution,LName=@LName,MName=@MName where Id=@Id 
else 
begin 
    INSERT INTO tbl_AuthorDetails VALUES(@Name,@Degree,@Title,@Email,@Institution,@CaseId,@LName,@MName) 
    Update tbl_AuthorDetails set CaseId=NULL where Id=@Id 
    exec CreateOtherAuthorsAccount @Name,@LName,@MName,@Degree,@Email 
    end 
end 

END 
set @uiID= (Select ID from [User] where Email=@Email) 
RETURN @uiID 

调用该函数唯一键约束的：

objGetBaseCase.Update_U_Anonymoususerdetails(GridView1, Convert.ToInt32(Request.QueryString[0])); 

Answer 1

这是因为同一email记录在数据库中已存在。并且数据库对电子邮件字段有一个限制，该字段中的每个条目应该是独特的，您将要插入数据的表中。

编辑：如果这个数据是由用户提供的，那么你需要抓住这个例外并显示一条消息给用户“具有相同的电子邮件地址在系统中已经存在的记录。”并允许他/她重新输入电子邮件字段的数据。

Answer 2

为了解决这个问题，你可以检查邮件是否已经存在：

IF NOT EXISTS (SELECT * FROM tbl_AuthorDetails where Email = @Email) 
BEGIN 
    Update tbl_AuthorDetails set Name=@Name,Degree=@Degree,Title=@Title,Email=@Email,Institution=@Institution,LName=@LName,MName=@MName where Id=@Id 
END