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C# 带有连接和字符串连接的查询_C#_Sql_.net - Fatal编程技术网

C# 带有连接和字符串连接的查询

C# 带有连接和字符串连接的查询,c#,sql,.net,C#,Sql,.net,我是C#的新手,来自VB6。有人知道为什么这个查询在C#中不起作用吗 我认为您的SQL语法不正确,请尝试此语法 "SELECT S.idGroup, S.idStatement, P1.nameLast " + "FROM STATEMENTS S LEFT JOIN GROUPS G on G.id = S.idGroup " + "LEFT JOIN People P1 on P1.id = G.idContactPerson " + "WHERE S.idTrip = @idTrip";

我是C#的新手,来自VB6。有人知道为什么这个查询在C#中不起作用吗


我认为您的SQL语法不正确,请尝试此语法

"SELECT S.idGroup, S.idStatement, P1.nameLast " +
"FROM STATEMENTS S LEFT JOIN GROUPS G on G.id = S.idGroup " +
"LEFT JOIN People P1 on P1.id = G.idContactPerson " +
"WHERE S.idTrip = @idTrip";

如果必须以这种方式构建SQL,请使用StringBuilder类构建命令字符串

Command.CommandText = @"SELECT S.idGroup, S.idStatement, P1.nameLast 
                      FROM STATEMENTS S LEFT JOIN GROUPS G on G.id = S.idGroup 
                      LEFT JOIN People P1 on P1.id = G.idContactPerson 
                      WHERE S.idTrip = " @idTrip;

试试这个语法

错误是什么?你现在怎么知道这不起作用了?你收到了什么错误信息,如果有的话?或者,更一般地说:这段代码会发生什么,应该发生什么?不对不起,它现在神秘地工作了!你真的不应该做所有的字符串连接,只是使用一个字符串文字。除此之外,这真的与C无关。
Command.CommandText = @"SELECT S.idGroup, S.idStatement, P1.nameLast 
                      FROM STATEMENTS S LEFT JOIN GROUPS G on G.id = S.idGroup 
                      LEFT JOIN People P1 on P1.id = G.idContactPerson 
                      WHERE S.idTrip = " @idTrip;