在设置插入查询之前帮助设置计数查询计数查询 [英] help in seting the count query count query before insert query

问题描述

我有一个查询要向用户分配角色

I have a query to assign roles t users

MAcmd.CommandText = "INSERT INTO ROLES (UserId,GroupId) SELECT UserId,GroupId FROM Users, Groups WHERE username= '" + TextBox1.Text + "' AND rolename='" + TextBox2.Text + "'";

我想实施count sql查询，以使记录不会重复保存在
但是我不知道如何在C#中做到这一点.
例如，我找到了一个存储过程..

例如

i want to implement count sql query so that the record not repeately save in
but i don''t know how to do it in C#.
e.g i found a stored procedure..

e.g

SELECT @Count = Count(UserID) FROM UserRoles WHERE
        RoleID = @RoleID AND UserID = @UserID
IF @Count = 0
		INSERT INTO UserRoles(UserID, RoleID)
		VALUES(@UserID, @RoleID)

谁能帮我写计数查询...如上所述，用于查询的存储过程.

can anyone help me to write count query ...as above store procedure for my query.

推荐答案

"INSERT INTO ROLES (UserId,GroupId) SELECT UserId,GroupId FROM Users, Groups WHERE username= ''" + TextBox1.Text + "'' AND rolename=''" + TextBox2.Text + "''";

仅供参考，请不要为此编写代码链接，这将在您的应用程序中创建SQL注入.请改用命令参数.
仅供参考:
SQL注入简介 [

FYI, Please don''t write code link this, This will create SQL Injection in your application. Use Command Parameter instead.
Just for your reference :
Introduction to SQL Injection[^]

MAcmd.CommandText =从UserRoles哪里选择Count(UserID)
RoleID = @RoleID和UserID = @UserID"
MAcmd.ExecuteScalar()

检查ExceuteScalar的retun值并执行插入脚本

MAcmd.CommandText = SELECT Count(UserID) FROM UserRoles WHERE
RoleID = @RoleID AND UserID = @UserID"
MAcmd.ExecuteScalar()

Check the retun value of ExceuteScalar and execute the insert scripts

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