2.1 MQL的標準查詢

var mm=ClassSet.Select(ClassSet.ClassID,ClassSet.ClassName).

Where(ClassSet.ClassName.Contains("s").And(ClassSet.ClassID.BiggerThan(9)));

SELECT [Class].[ClassID],[Class].[ClassName] FROM [Class] WHERE [Class].[ClassName] LIKE @p1  AND  [Class].[ClassID]>@p2
@p1=%s%
@p2=9

2.2 MQL的巢狀查詢(含有Top查詢:支援mysql、oracle、postgreSQL、sqlserver、sqlite)

var qiantao=ScoreSet.SelectAll().Where(
                    ScoreSet.UserID.In(UserSet.Select(UserSet.UserID).Where(
                        UserSet.ClassID.In(
                        ClassSet.Select(ClassSet.ClassID).Where(
                                ClassSet.ClassName.Equal(c.ClassName).And(ClassSet.ClassID.BiggerThan(0))
                            )
                        )
                    )
                  ) 
                ).Top(1);   SELECT TOP 1 [Score].* FROM [Score] WHERE [Score].[UserID] IN (SELECT [User].[UserID] FROM [User] WHERE [User].[ClassID] IN (SELECT [Class].[ClassID] FROM [Class] WHERE [Class].[ClassName]

[email protected]  AND  [Class].[ClassID]>@p2 ) )
@p1=綜合測試ClassName2
@p2=0

2.3 MQL的分組查詢

var mql=ScoreSet.Select(ScoreSet.ScoreM.Sum().AS("sum"),ScoreSet.TypeName).

Where(ScoreSet.ScoreM.BiggerThanOrEqual(100)).

GroupBy(ScoreSet.TypeName).

Having(ScoreSet.ScoreM.Sum().BiggerThan(300));

SELECT SUM([Score].[ScoreM]) AS 'sum',[Score].[TypeName] FROM [Score] WHERE  [Score].[ScoreM]>[email protected]  GROUP BY [Score].[TypeName]  HAVING  SUM([Score].[ScoreM])>@p2
@p1=100
@p2=300

2.4 MQL的連線查詢

var m1=ClassSet.Select(ClassSet.ClassID,ClassSet.ClassName)
                    .LeftJoin(
                    UserSet.Select(UserSet.UserID))
                    .ON(ClassSet.ClassID.Equal(UserSet.UserID))
                    .Where(UserSet.UserID.BiggerThan(9)); SELECT [Class].[ClassID],[Class].[ClassName],[User].[UserID] FROM [Class] LEFT JOIN [User] ON [Class].[ClassID]=[User].[UserID]  WHERE  [User].[UserID]>@p1
@p1=9

2.5 MQL的Union查詢

var mql=ClassSet.SelectAll().Where(ClassSet.ClassID.BiggerThan(1))
                    .Union(ClassSet.SelectAll().Where(ClassSet.ClassID.BiggerThan(2)));   var mql=ClassSet.SelectAll().Where(ClassSet.ClassID.BiggerThan(1))
                    .UnionAll(ClassSet.SelectAll().Where(ClassSet.ClassID.BiggerThan(2))); SELECT [Class].* FROM [Class] WHERE  [Class].[ClassID]>@p1  UNION  SELECT [Class].* FROM [Class] WHERE  [Class].[ClassID]>@p2
@p1=1
@p2=2 SELECT [Class].* FROM [Class] WHERE  [Class].[ClassID]>@p1  UNION ALL SELECT [Class].* FROM [Class] WHERE  [Class].[ClassID]>@p2
@p1=1
@p2=2

2.6 MQL的使用預覽

public static void Main(string[] args)
        {
            
            using (var db=Db.CreateDefaultDb()) {
                db.TransactionEnabled=true;
                db.DebugEnabled=true;
                Console.WriteLine("---------------巢狀查詢---------------------");
                var qiantao=ScoreSet.SelectAll().Where(
                    ScoreSet.UserID.In(UserSet.Select(UserSet.UserID).Where(
                        UserSet.ClassID.In(
                        ClassSet.Select(ClassSet.ClassID).Where(
                                ClassSet.ClassName.Equal(c.ClassName).And(ClassSet.ClassID.BiggerThan(0))
                            )
                        )
                    )
                  ) 
                ).Top(1);
               
                Console.WriteLine("---------------分組查詢---------------------");
                var mql=ScoreSet.Select(ScoreSet.ScoreM.Sum().AS("sum"),ScoreSet.TypeName).Where(ScoreSet.ScoreM.BiggerThanOrEqual(100)).GroupBy(ScoreSet.TypeName).Having(ScoreSet.ScoreM.Sum().BiggerThan(300));
              
                Console.WriteLine("---------------連線查詢---------------------");
                var m1=ClassSet.Select(ClassSet.ClassID,ClassSet.ClassName)
                    .LeftJoin(
                    UserSet.Select(UserSet.UserID))
                    .ON(ClassSet.ClassID.Equal(UserSet.UserID))
                    .Where(UserSet.UserID.BiggerThan(9));

            }
            Console.WriteLine("---------------Union測試---------------------");
            using (var db=Db.CreateDefaultDb()) {
                db.TransactionEnabled=true;
                db.DebugEnabled=true;
                
                var mql=ClassSet.SelectAll().Where(ClassSet.ClassID.BiggerThan(1))
                    .Union(ClassSet.SelectAll().Where(ClassSet.ClassID.BiggerThan(2))); 

            }
        }