Category Archives: ???

SQL Server, Oracle, MySql, Sqlite

??Oracle???

by 
SELECT a.File#, a.Name, a.Bytes / 1024 / 1024 Currentmb, Ceil(Hwm * a.Block_Size) / 1024 / 1024 Resizeto, (a.Bytes -
        Hwm *
        a.Block_Size) / 1024 / 1024 Releasemb, 'alter database datafile ''' ||
        a.Name || ''' resize ' ||
        Ceil(Hwm * a.Block_Size / 1024 / 1024) || 'M;' Resizecmd
FROM   V$datafile a, (SELECT File_Id, MAX(Block_Id + Blocks - 1) Hwm
         FROM   Dba_Extents
         GROUP  BY File_Id) b
WHERE  a.File# = b.File_Id(+) AND (a.Bytes - Hwm * Block_Size) > 0

 

Oracle UUID SYS_GUID

by

Oracle???RAW(16)??SYS_GUID()??????????(byte order)????GUID?????

??GUID? 265B113F-0E9D-F44D-A9D4-18BC4D3E836C

RAW(16) ? 3F115B26 9D0E 4DF4 A9D4 18BC4D3E836C ??????????????????

???????????????????????

SELECT Regexp_Replace(Lower(Sys_Guid()),
                       '(.{2})(.{2})(.{2})(.{2})(.{2})(.{2})(.{2})(.{2})(.{4})',
                       '\4\3\2\1-\6\5-\8\7-\9-') AS Dummy
FROM   Dual
CONNECT BY Rownum <= 20;

 

SQL Server——????fn_Split??

by

??SQL2000??ntext?bug?

CREATE FUNCTION [dbo].[Fn_split] (@expression NTEXT,
                                  @delimiter  NVARCHAR(2) = ',')
RETURNS @expressionstable TABLE (
  [DUMMY] NVARCHAR(4000))
AS
  BEGIN
      DECLARE @currentindex INT
      DECLARE @nextindex INT
      DECLARE @returntext NVARCHAR(4000)
      DECLARE @datalength INT
      IF @expression IS NULL
        BEGIN
            INSERT INTO @expressionstable
                        ([DUMMY])
            VALUES      (NULL)
        END
      ELSE
        BEGIN
            SELECT @datalength = Datalength(@expression) / 2
            IF @datalength = 0
              INSERT INTO @expressionstable
                          ([DUMMY])
              VALUES      ('')
            ELSE
              BEGIN
                  SELECT @currentindex = 1
                  WHILE( @currentindex <= @datalength )
                    BEGIN
                        SELECT @nextindex = Charindex(@delimiter, Substring(@expression, @currentindex, 4000))
                                            + @currentindex
                        /*????Charindex????????8000??????????????*/
                        IF( @nextindex = @currentindex )
                          SELECT @nextindex = @currentindex + @datalength
                        SELECT @returntext = Substring(@expression, @currentindex - 1, @nextindex - @currentindex)
                        INSERT INTO @expressionstable
                                    ([DUMMY])
                        VALUES      (@returntext)
                        SELECT @currentindex = @nextindex + 1
                    END
              END
        END
      RETURN
  END

 

CREATE FUNCTION [dbo].[Fn_split] (@str       VARCHAR(MAX),
                                  @separator VARCHAR(10))
RETURNS TABLE
AS
    RETURN
      (SELECT T0.DUMMY
       FROM   ( (SELECT [DUMMY] = CONVERT(XML, '<DUMMY>'
                                             + Replace(@str, @separator, '</DUMMY><DUMMY>')
                                             + '</DUMMY>')) T1
                OUTER APPLY (SELECT DUMMY = N.v.value('.', 'NVARCHAR(4000)')
                             FROM   T1.[DUMMY].nodes('/DUMMY') N(v)) T0 ))

???

SELECT * FROM fn_split('1,2,3,4,5', ',');

??Transact-SQL????

by

Transact-SQL????????

RAND:?????? 0 ? 1???? 0 ? 1??????? float ??????? seed?? SQL Server ????????????? ???????????? RAND() ???????????????????????????? RAND()?? RAND() ??????????????????? RAND() ???????

NEWID:?? uniqueidentifier ???????NEWID ???????????????

CHECKSUM:??????????????????????????????????CHECKSUM ??????????????????????????????? CHECKSUM ??(???????????????)

??RAND()???????????? RAND() ????????????????????SELECT???????????????????????????????????????

?????CHECKSUM(NEWID())??RAND(CHECKSUM(NEWID()))????

?????????????

[????]??????SQL????????????-??????

by

????????SQL?????????????????????????????

???????????????

e_class_table

CREATE TABLE [dbo].[E_Classes] ([ClassID] varchar(12) NOT NULL ,[BeginDate] date NULL ,[EndDate] date NULL ,[StudentCount] smallint NULL);
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'01', N'2011-10-07', N'2012-03-11', N'49');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'02', N'2012-04-05', N'2012-06-20', N'23');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'03', N'2012-05-01', N'2012-07-03', N'46');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'04', N'2013-03-08', N'2013-06-12', N'42');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'05', N'2013-09-19', N'2013-10-26', N'78');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'06', N'2013-11-21', N'2014-01-09', N'44');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'07', N'2013-12-27', N'2014-02-06', N'36');
INSERT INTO [dbo].[E_Classes] ([ClassID], [BeginDate], [EndDate], [StudentCount]) VALUES (N'08', N'2014-02-28', N'2014-06-20', N'52');

???????????????????????????

class_total

????? ????????????*????????2014?01????? ??06? 2014-01-01~2014-01-09??9?*44?=396?? ??? ??07?2014-01-01~2014-01-31??31?*36?=1116?????2014?01????? 396+1116=1512????

?????????????????????????????????:

CREATE TABLE [dbo].[E_Sequence]([Sequence_ID] [int] IDENTITY(1,1) NOT NULL, CONSTRAINT [PK_E_Sequence] PRIMARY KEY CLUSTERED ([Sequence_ID] ASC)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]);
SET IDENTITY_INSERT [dbo].[E_Sequence] ON
INSERT INTO [dbo].[E_Sequence] (Sequence_ID)
SELECT number FROM [master]..[spt_values] WHERE  type = 'P'
UNION ALL
SELECT number + 2048 FROM [master]..[spt_values] WHERE  type = 'P'
SET IDENTITY_INSERT [dbo].[E_Sequence] OFF

??????????????????????????

SELECT Dateadd(day, Sequence_id, '2011-1-1') AS Class_Date FROM E_Sequence

????????????????2011?01?01????4000?????????????????????????????

SELECT Year(Class_Date)  AS Class_Year,
       Month(Class_Date) AS Class_Month,
       StudentCount
FROM   (SELECT Dateadd(day, Sequence_id, '2011-1-1') AS Class_Date
        FROM   E_Sequence) t1,
       E_Classes t2
WHERE  t1.Class_Date BETWEEN t2.BeginDate AND t2.EndDate

?????

class_split

OK??????????????“?”?????“?”?????“???”????????????????????????????SQL2000?????Case When End??

SELECT Class_Year      AS ??,
       Isnull([1], 0)  AS ??,
       Isnull([2], 0)  AS ??,
       Isnull([3], 0)  AS ??,
       Isnull([4], 0)  AS ??,
       Isnull([5], 0)  AS ??,
       Isnull([6], 0)  AS ??,
       Isnull([7], 0)  AS ??,
       Isnull([8], 0)  AS ??,
       Isnull([9], 0)  AS ??,
       Isnull([10], 0) AS ??,
       Isnull([11], 0) AS ???,
       Isnull([12], 0) AS ???
FROM   (SELECT Year(Class_Date)  AS Class_Year,
               Month(Class_Date) AS Class_Month,
               studentcount
        FROM   (SELECT Dateadd(day, Sequence_id, '2011-1-1') AS Class_Date
                FROM   E_Sequence) t1,
               e_classes t2
        WHERE  t1.Class_Date BETWEEN t2.begindate AND t2.enddate) t 
        PIVOT (Sum(studentcount) FOR Class_Month IN
        ([1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12])) tpivot

???????????????????????????

???

SELECT Dateadd(day, Sequence_id, '2011-1-1') AS Class_Date FROM E_Sequence

????????????????????????????????????????????????

???????

????2012?07?16??2013?06?15??????????????????

[????]??????SQL???????????????

by

????????SQL?????????????????????????????

????????????????????????????????

CREATE TABLE [dbo].[PerHalfHour]([CallInTime] [smalldatetime] NULL, [Result] [int] NULL);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 08:20:00', 2);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 08:38:00', 2);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 08:43:00', 2);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 08:49:00', 2);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:07:00', 2);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:07:00', 1);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:10:00', 1);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:16:00', 1);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:41:00', 1);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:44:00', 1);
INSERT [dbo].[PerHalfHour] ([CallInTime], [Result]) VALUES ('2014-01-01 09:52:00', 1);

?????????????

SELECT CallInTime_Hour,
       CallInTime_Minute,
       Count(*) AS CallInTime_Count
FROM   (SELECT Datepart(HOUR, CallInTime)             AS CallInTime_Hour,
               Datepart(MINUTE, CallInTime) / 30 * 30 AS CallInTime_Minute
			   /*??SQL ??/??=?? ??????????*/
        FROM   [PerHalfHour]
        WHERE  CallInTime >= '2014-01-01'
               AND CallInTime < '2014-01-02') t
GROUP  BY CallInTime_Hour,
          CallInTime_Minute
ORDER  BY CallInTime_Hour,
          CallInTime_Minute

??????
callintime
??????????????24???????????????????????

CREATE TABLE [dbo].[Sequence_HalfHour]([sequence_time] [nvarchar](20) NULL,[sequence_hour] [int] NULL,[sequence_minute] [int] NOT NULL);
INSERT [dbo].[Sequence_HalfHour] ([sequence_time], [sequence_hour], [sequence_minute]) VALUES (N'00:00:00~00:29:59', 0, 0);
INSERT [dbo].[Sequence_HalfHour] ([sequence_time], [sequence_hour], [sequence_minute]) VALUES (N'00:30:00~00:59:59', 0, 30);
INSERT [dbo].[Sequence_HalfHour] ([sequence_time], [sequence_hour], [sequence_minute]) VALUES (N'01:00:00~01:29:59', 1, 0);
INSERT [dbo].[Sequence_HalfHour] ([sequence_time], [sequence_hour], [sequence_minute]) VALUES (N'01:30:00~01:59:59', 1, 30);
...
INSERT [dbo].[Sequence_HalfHour] ([sequence_time], [sequence_hour], [sequence_minute]) VALUES (N'23:00:00~23:29:59', 23, 0);
INSERT [dbo].[Sequence_HalfHour] ([sequence_time], [sequence_hour], [sequence_minute]) VALUES (N'23:30:00~23:59:59', 23, 30);

?????????Left Join??????OK?

SELECT t0.sequence_time            AS ???,
       Isnull(CallInTime_Count, 0) AS ??
FROM   sequence_halfhour t0
       LEFT JOIN (SELECT CallInTime_Hour,
                         CallInTime_Minute,
                         Count(*) AS CallInTime_Count
                  FROM   (SELECT Datepart(HOUR, CallInTime)             AS CallInTime_Hour,
                                 Datepart(MINUTE, CallInTime) / 30 * 30 AS CallInTime_Minute
                          /*??SQL ??/??=?? ??????????*/
                          FROM   [PerHalfHour]
                          WHERE  CallInTime >= '2014-01-01'
                                 AND CallInTime < '2014-01-02') t
                  GROUP  BY CallInTime_Hour,
                            CallInTime_Minute) t1
         ON t0.sequence_hour = t1.CallInTime_Hour
            AND t0.sequence_minute = t1.CallInTime_Minute

?????

total_callintime

?????

???????Result?????SQL?????????

callintime_result