The*_*iot 4 c# sql arrays wcf entity-framework
我正在使用EF构建一个WCF服务到Microsoft SQL Server但仍然收到以下错误:
附加信息:从对象类型System.Data.Objects.ObjectParameter到已知的托管提供程序本机类型不存在映射.
在这个查询:
string ID = "XXID";
string Sql = @"SELECT * FROM @Table WHERE " + ID + " LIKE '@SearchTerm'";
ObjectParameter[] Parameters = new ObjectParameter[2];
Parameters[0] = new ObjectParameter("Table", Table);
Parameters[1] = new ObjectParameter("SearchTerm", SearchTerm);
using (var Context = new XXEntities())
{
Context.Database.Connection.Open();
IEnumerable<string> Query = Context.Database.SqlQuery<string>(Sql, Parameters);
string[] Results = Query.ToArray();
Context.Database.Connection.Close();
return Results;
}
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我已经在SQL Server上测试了查询,它按预期工作 - 返回匹配ID的记录.
尝试使用sql参数instaed of object parameter
IEnumerable<string> Query = Context.Database.SqlQuery<string>(Sql,
new SqlParameter("Table", Table),
new SqlParameter("SearchTerm", SearchTerm));
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从理论上讲,你可以操作sql而不需要像这样的任何发送参数
IEnumerable<string> Query = Context.Database.SqlQuery<string>("SELECT * FROM "+Table+" WHERE " + ID + " LIKE '"+SearchTerm+"'");
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