在EF 4和EF 3.5 SP1中，我们可以使用ToTraceString()方法得到EF查询所生成的SQL。
using (var context = new TestDBEntities())
{
var query = from p in context.Parents
where p.Name == "zhaokun"
select p; ObjectQuery<Parent> parents = query as ObjectQuery<Parent>;
if (parents != null)
{
string sql = parents.ToTraceString();
}
}
totracestring
这里所生成的SQL为：
[Extent1].[ParentID] AS [ParentID],
[Extent1].[Name] AS [Name]
FROM [dbo].[Parent] AS [Extent1]
WHERE N'zhaokun'=[Extent1].[Name]
sqlone
在EF 4.1中，我们可以直接调用DbQuery<>的ToString()方法得到所生成的SQL。
using (var context = new MyDbContext())
{
var people = from p in context.People
where p.PersonID >
select p; string sql = people.ToString();
}
tostring
所生成的SQL是：
SELECT
[Extent1].[PersonID] AS [PersonID],
[Extent1].[Name] AS [Name]
FROM [dbo].[People] AS [Extent1]
WHERE [Extent1].[PersonID] >
sqltwo
这里的ToString()方法其实也就是调用了ObjectQuery<>的ToTraceString()方法。 DbQuery<>.ToString() ==> System.Data.Entity.Internal.Linq.InternalQuery<>.ToString()方法，此方法 在.NET Reflector得到的实现是这样的：
public override string ToString()
{
return this._objectQuery.ToTraceString();
}
tostring（）
看书得到！