I have following values in my table:
ABC
ABC1
ABC2
ABC3 and so on...
ABC11
ABC12
ABC13 and so on..
ABC20
ABC21
ABC22 and so on..
So basically what I have is any string value (not always ABC, any string value) that can either be followed by the number or it may just be a string without the number.
When I do select * from table order by my column asc I get following results:
ABC
ABC1
ABC11
ABC12
ABC13
ABC2
ABC20
ABC21
ABC22
ABC3
ABC31
ABC32
I need it sorted numerically:
ABC
ABC1
ABC2
ABC3
ABC11
ABC12
ABC13
ABC20
ABC21
ABC22
ABC31
ABC32
How can this be accomplished?
You can do it using PATINDEX() function like below :
select * from Test
order by CAST(SUBSTRING(Name + '0', PATINDEX('%[0-9]%', Name + '0'), LEN(Name + '0')) AS INT)
SQL Fiddle Demo
If you have numbers in middle of the string then you need to create small user defined function to get number from string and sort data based on that number like below :
CREATE FUNCTION dbo.fnGetNumberFromString (#strInput VARCHAR(255))
RETURNS VARCHAR(255)
AS
BEGIN
DECLARE #intNumber int
SET #intNumber = PATINDEX('%[^0-9]%', #strInput)
WHILE #intNumber > 0
BEGIN
SET #strInput = STUFF(#strInput, #intNumber, 1, '')
SET #intNumber = PATINDEX('%[^0-9]%', #strInput)
END
RETURN ISNULL(#strInput,0)
END
GO
You can sort data by :
select Name from Test order by dbo.fnGetNumberFromString(Name), Name
(based on answers from #shenhengbin and #EchO to this question)
The following is what I call a "clean hack". Assuming you are ordering on column Col1:
ORDER BY LEN(Col1), Col1
It is a hack, although I'd personally feel proud using it.
In order by statement, prepend enough zeros with when value contains any number in it to make all alphanumerica value same length
SELECT ColName
FROM TableName
ORDER BY
CASE WHEN ColName like '%[0-9]%'
THEN Replicate('0', 100 - Len(ColName)) + ColName
ELSE ColName END
You could remove the first three characters and cast the rest to int
SELECT Value,
Num=CAST(RIGHT(Value, LEN(Value) - 3) AS int)
FROM dbo.TableName
ORDER BY Num
Demo
You could adapt the function RemoveNonAlphaCharacters in this answer to filter out everything except numbers, and then use an ORDER BY using that function.
Using Standard SQL ONLY this query demonstrates how you can ODER BY either the numbers found to be contained at the Beginning or the End of the string. The query also shows how you could then look at the remaining 'inner' portion of the string to see if there are any numbers contained there. Knowing if there are numbers contained within the string could be useful if further processing is necessary.
WITH stringNumberData AS
( /* Build up Fake data with Numbers at the Beginning, End and Middle of the string */
SELECT 1 AS uniqueKey, 'ABC' AS NumberFromString UNION ALL
SELECT 2 AS uniqueKey, 'ABC1' AS NumberFromString UNION ALL
SELECT 3 AS uniqueKey, 'ABC2' AS NumberFromString UNION ALL
SELECT 4 AS uniqueKey, 'ABC3' AS NumberFromString UNION ALL
SELECT 5 AS uniqueKey, 'ABC10' AS NumberFromString UNION ALL
SELECT 6 AS uniqueKey, 'ABC11' AS NumberFromString UNION ALL
SELECT 7 AS uniqueKey, 'ABC12' AS NumberFromString UNION ALL
SELECT 8 AS uniqueKey, 'ABC20' AS NumberFromString UNION ALL
SELECT 9 AS uniqueKey, 'ABC21' AS NumberFromString UNION ALL
SELECT 10 AS uniqueKey, 'ABC22' AS NumberFromString UNION ALL
SELECT 11 AS uniqueKey, 'ABC30' AS NumberFromString UNION ALL
SELECT 12 AS uniqueKey, 'ABC31' AS NumberFromString UNION ALL
SELECT 13 AS uniqueKey, 'ABC32' AS NumberFromString UNION ALL
SELECT 14 AS uniqueKey, '1ABC' AS NumberFromString UNION ALL
SELECT 15 AS uniqueKey, '2ABC' AS NumberFromString UNION ALL
SELECT 16 AS uniqueKey, '3ABC' AS NumberFromString UNION ALL
SELECT 17 AS uniqueKey, '10ABC' AS NumberFromString UNION ALL
SELECT 18 AS uniqueKey, '11BC' AS NumberFromString UNION ALL
SELECT 19 AS uniqueKey, '12ABC' AS NumberFromString UNION ALL
SELECT 20 AS uniqueKey, '10ABC18' AS NumberFromString UNION ALL
SELECT 21 AS uniqueKey, '11BC52' AS NumberFromString UNION ALL
SELECT 22 AS uniqueKey, '12ABC42' AS NumberFromString UNION ALL
SELECT 23 AS uniqueKey, 'A3BC18' AS NumberFromString UNION ALL
SELECT 24 AS uniqueKey, 'B3C52' AS NumberFromString UNION ALL
SELECT 25 AS uniqueKey, '12AB3C' AS NumberFromString UNION ALL
SELECT 26 AS uniqueKey, 'A3BC' AS NumberFromString UNION ALL
SELECT 27 AS uniqueKey, 'AB2C' AS NumberFromString UNION ALL
SELECT 28 AS uniqueKey, 'ABC85D' AS NumberFromString
)
SELECT d.uniqueKey, d.NumberFromString
/* Extract numerical values contained on the LEFT of the String by finding the index of the first non number */
, LEFT(d.NumberFromString, PATINDEX('%[^0-9]%', d.NumberFromString) -1) AS 'Left Numbers Extraction'
/* Extract numerical data contained on the RIGHT of the String */
, RIGHT(d.NumberFromString, PATINDEX('%[^0-9]%', REVERSE(d.NumberFromString)) - 1 ) AS 'Right Numbers Extraction'
/* The below checks inside the Inner string to determine if numbers exists within it. Could be used for further processing if further extraction is necessary */
, PATINDEX('%[0-9]%',
SUBSTRING(d.NumberFromString /*, Start Pos, Length to Extract) */
, PATINDEX('%[^0-9]%', d.NumberFromString) /* Start Pos is first left non number */
/* The below obtains the length of the Inner String so it can be extracted */
, LEN(d.NumberFromString) - ((PATINDEX('%[^0-9]%', d.NumberFromString) -1 )) - (PATINDEX('%[^0-9]%', REVERSE(d.NumberFromString)) -1) /* (String Length) - (LEFT Numbers) - (RIGHT Numbers) */
)) AS innerNumExists
/* The two lines below tell us if there exists a number at the Beginning and/or End of the string */
, PATINDEX('%[0-9]%', LEFT(d.NumberFromString, 1)) AS leftNumExists
, PATINDEX('%[0-9]%', RIGHT(d.NumberFromString, 1)) AS rightNumExists
/* Locates and returns the index of the very first number located in the string from Left to Right */
, PATINDEX('%[^0-9]%', d.NumberFromString) AS firstLeftNonNum_index
/* Locates and returns the index of the very first number located in the string from Right to Left */
, LEN(d.NumberFromString) - (PATINDEX('%[^0-9]%', REVERSE(d.NumberFromString)) -1 ) AS firstRightNonNum_index
/* Get the length of the numbers existing from Right to Left up to the first non numeric character */
, PATINDEX('%[^0-9]%', REVERSE(d.NumberFromString)) -1 AS rightStringLen
FROM stringNumberData d
ORDER BY
/* Ordering first by numbers found on the LEFT of the string */
CAST(LEFT(d.NumberFromString, PATINDEX('%[^0-9]%', d.NumberFromString) -1) AS INT )
/* Ordering second by numbers found on the RIGHT of the string */
, CAST(RIGHT(d.NumberFromString, PATINDEX('%[^0-9]%', REVERSE(d.NumberFromString)) - 1 ) AS INT )
;
Here's a simple to understand example for those using SQL Server 17+.
DECLARE #Data table ( val varchar(10) );
INSERT INTO #Data VALUES
( 'ABC' ),( 'ABC1' ),( 'ABC11' ),( 'ABC12' ),( 'ABC13' ),( 'ABC2' ), ( 'B1C' ),
( 'ABC20' ),( 'ABC21' ),( 'ABC22' ),( 'ABC3' ),( 'ABC31' ),( 'ABC32' );
SELECT val FROM #Data AS d
CROSS APPLY (
SELECT CAST ( TRANSLATE ( d.val, 'abcdefghijklmnopqrstuvwxyz', ' ' ) AS int ) AS Num
) AS x
ORDER BY
LEFT ( val, 1 ), Num;
Returns
+-------+
| val |
+-------+
| ABC |
| ABC1 |
| ABC2 |
| ABC3 |
| ABC11 |
| ABC12 |
| ABC13 |
| ABC20 |
| ABC21 |
| ABC22 |
| ABC31 |
| ABC32 |
| B1C |
+-------+
SQL Server's TRANSLATE takes three parameters: inputString, characters, translations.
The inputString in your case is your column name.
The characters are the values you're looking to replace, in this case the alphabet.
The translations are the values to replace with. This string must be equal in length to the characters--hence the empty string that's 26 spaces long.
And finally, using CAST ignores the spaces and allows the remaining value to be sorted as an int.
You can read about TRANSLATE here:
https://learn.microsoft.com/en-us/sql/t-sql/functions/translate-transact-sql?view=sql-server-ver15
Related
I'm just trying to understand CTE and recursion to solve an issue that I would previously have used a cursor for.
create table ##ACC (
AccNo int,
Property char
)
Insert into ##ACC
VALUES (1,'A'),(1,'B'),(2,'A'),(2,'C'),(3,'C'),(4,'D')
What I'm trying to achieve is to get a list of all AccNo's, and all AccNo's they're related to via Property. So my expected results are
PrimaryAccNo | LinkedAccNo
1 | 1
1 | 2
1 | 3
2 | 1
2 | 2
2 | 3
3 | 1
3 | 2
3 | 3
4 | 4
I've attempted the following code and variations but I either get 4 results (PrimaryAccNo=LinkedAccNo) only or I hit 100 recursions.
WITH Groups(PrimaryAccNo, LinkedAccNo)
AS
(
Select distinct AccNo, AccNo from ##ACC
UNION ALL
Select g.PrimaryAccNo, p.AccNo from
##ACC p inner join Groups g on p.AccNo=g.LinkedAccNo
inner join ##ACC pp on p.Property=pp.Property
where p.AccNo<> pp.AccNo
)
Select PrimaryAccNo,LinkedAccNo
from Groups
What am I doing wrong?
You're running into an infinite loop caused by cycles within your data, e.g.: 1 > 2 > 3 > 2 > ... . The solution is to keep track of the rows that have already been "consumed". Due to limitations in CTEs, this has to be done by including the history within each CTE row, e.g. by assembling the path followed to arrive at each row. You can uncomment the , Path on the final select to see what is going on.
-- Sample data.
declare #ACC as Table ( AccNo Int, Property Char );
insert into #ACC values
( 1, 'A' ), ( 1, 'B' ), ( 2, 'A' ), ( 2, 'C' ), ( 3, 'C' ), ( 4, 'D' );
select * from #ACC;
-- Recursive CTE.
with Groups as (
select distinct AccNo, AccNo as LinkedAccNo,
Cast( '|' + Cast( AccNo as VarChar(10) ) + '|' as VarChar(1024) ) as Path
from #ACC
union all
select G.AccNo, A.AccNo, Cast( Path + Cast( A.AccNo as VarChar(10) ) + '|' as VarChar(1024) )
from Groups as G inner join -- Take the latest round of new rows ...
#ACC as AP on AP.AccNo = G.LinkedAccNo inner join -- ... and get the Property for each ...
#ACC as A on A.Property = AP.Property -- ... to find new linked rows.
where G.Path not like '%|' + Cast( A.AccNo as VarChar(10) ) + '|%' )
select AccNo, LinkedAccNo -- , Path
from Groups
order by AccNo, LinkedAccNo;
Another approach similar to yours but differs in the following:
The property value is included in the recursive CTE so that it can be used later
The < is used to prevent duplicates and the resulting infinite recursion
Another CTE is added AccGroups to provide the mirror of the relations
A demo fiddle has been included below:
CREATE TABLE ##ACC (
AccNo int,
Property char
);
INSERT INTO ##ACC
VALUES (1,'A'),(1,'B'),(2,'A'),(2,'C'),(3,'C'),(4,'D');
WITH Groups(PrimaryAccNo, LinkedAccNo, Property) AS (
SELECT AccNo, AccNo, Property FROM ##ACC
UNION ALL
SELECT g.PrimaryAccNo, pp.AccNo, pp.Property
FROM Groups g
INNER JOIN ##ACC p ON g.Property=p.Property AND
g.LinkedAccNo < p.AccNo
INNER JOIN ##ACC pp ON p.AccNo = pp.AccNo
),
AccGroups AS (
SELECT DISTINCT * FROM (
SELECT PrimaryAccNo, LinkedAccNo FROM Groups
UNION ALL
SELECT LinkedAccNo, PrimaryAccNo FROM Groups
) t
)
SELECT * FROM AccGroups
ORDER BY PrimaryAccNo,LinkedAccNo
GO
PrimaryAccNo | LinkedAccNo
-----------: | ----------:
1 | 1
1 | 2
1 | 3
2 | 1
2 | 2
2 | 3
3 | 1
3 | 2
3 | 3
4 | 4
db<>fiddle here
I have a dataset already sorted by a window function in sql:
ROW_NUMBER() OVER (PARTITION BY LOAN_NUMBER, CAST(CREATED_DATE AS DATE) ORDER BY LOAN_NUMBER, CREATED_DATE) AS ROW_IDX
shown as above. I wonder if there's a way that reset the ROW_IDX when the CREATED_DATE has begun to have a value with over one hour gap to the minimum datetime in a specific day.
For example, the row index for row 3 should be 1 because the time gap between 2016-11-03 15:39:16.000 and 2016-11-03 12:44:11.000 is over one hour.And row index of row 4 will be 2.
I've tried several ways to manipulate the datatime column, since the consideration is about 'gap' instead of moments of the day, no rounding methods worked perfectly.
Are mean ,when the gap more than 60 minutes, will restart at 1?
Which version are you use? If it is SQL Server 2012+, you can try this.
The following query is not satisfying, but wish can give you help.
Calculating the diff minutes between continuous two line.
Check the diff minutes whether greater than one hour
Get row number base on the gap time has same situation continuously.
Sorry if I can not describe clear. My english is not well.
;WITH tb(RptDate,ISSUE_ID,ACCOUNT,CREATED_DATE )AS(
select '2017-01-17','35775','76505156','2016-11-03 12:44:11.000' UNION
select '2017-01-17','35793','76505156','2016-11-03 12:51:43.000' UNION
-- select '2017-01-17','35793','76505156','2016-11-03 13:47:43.000' UNION
-- select '2017-01-17','35793','76505156','2016-11-03 14:45:43.000' UNION
select '2017-01-17','36097','76505156','2016-11-03 15:39:16.000' UNION
select '2017-01-17','36132','76505156','2016-11-03 15:52:51.000' UNION
select '2017-01-17','41391','76505156','2016-11-10 10:49:30.000'
)
SELECT *,ROW_NUMBER()OVER(PARTITION BY tt.ACCOUNT,a ORDER BY tt.ACCOUNT, rn) AS ROW_IDX FROM (
SELECT * ,rn-ROW_NUMBER () OVER (PARTITION BY ACCOUNT, CAST(CREATED_DATE AS DATE),n ORDER BY rn) AS a
FROM (
SELECT *, ROW_NUMBER()OVER(PARTITION BY ACCOUNT ORDER BY CREATED_DATE) AS rn
,CASE WHEN DATEDIFF(MINUTE, LAG(CREATED_DATE)OVER(PARTITION BY ACCOUNT ORDER BY CREATED_DATE),tb.CREATED_DATE)>60 THEN 1 ELSE 0 END AS n
,ISNULL(DATEDIFF(MINUTE, LAG(CREATED_DATE)OVER(PARTITION BY ACCOUNT ORDER BY CREATED_DATE),tb.CREATED_DATE),0) AS DiffMin
FROM tb
) AS t
) AS tt
ORDER BY rn
RptDate ISSUE_ID ACCOUNT CREATED_DATE rn n DiffMin a ROW_IDX
---------- -------- -------- ----------------------- -------------------- ----------- ----------- -------------------- --------------------
2017-01-17 35775 76505156 2016-11-03 12:44:11.000 1 0 0 0 1
2017-01-17 35793 76505156 2016-11-03 12:51:43.000 2 0 7 0 2
2017-01-17 36097 76505156 2016-11-03 15:39:16.000 3 1 168 2 1
2017-01-17 36132 76505156 2016-11-03 15:52:51.000 4 0 13 1 1
2017-01-17 41391 76505156 2016-11-10 10:49:30.000 5 1 9777 4 1
It is another script,Do not use the LAG function, Each step has a statement:
;WITH tb(RptDate,ISSUE_ID,ACCOUNT,CREATED_DATE )AS(
select '2017-01-17','35775','76505156','2016-11-03 12:44:11.000' UNION
select '2017-01-17','35793','76505156','2016-11-03 12:51:43.000' UNION
-- select '2017-01-17','35793','76505156','2016-11-03 13:47:43.000' UNION
-- select '2017-01-17','35793','76505156','2016-11-03 14:45:43.000' UNION
select '2017-01-17','36097','76505156','2016-11-03 15:39:16.000' UNION
select '2017-01-17','36132','76505156','2016-11-03 15:52:51.000' UNION
select '2017-01-17','41391','76505156','2016-11-10 10:49:30.000'
),t1 AS(
SELECT *, ROW_NUMBER()OVER(PARTITION BY ACCOUNT ORDER BY CREATED_DATE) AS rn FROM tb
),t2 AS (
SELECT t1.*,CASE WHEN DATEDIFF(MINUTE,tt.CREATED_DATE,t1.CREATED_DATE)>60 THEN 1 ELSE 0 END AS m
,t1.rn-ROW_NUMBER()OVER(PARTITION BY t1.ACCOUNT,CASE WHEN DATEDIFF(MINUTE,tt.CREATED_DATE,t1.CREATED_DATE)>60 THEN 1 ELSE 0 END ORDER BY t1.CREATED_DATE) AS a
FROM t1 LEFT JOIN t1 AS tt ON tt.ACCOUNT=t1.ACCOUNT AND tt.rn=t1.rn-1
),t3 AS(
SELECT *,ROW_NUMBER()OVER(PARTITION BY ACCOUNT,t2.a ORDER BY CREATED_DATE) AS ROW_IDX
FROM t2
)
SELECT * FROM t3
ORDER BY t3.ACCOUNT,t3.CREATED_DATE
I have a query with the columns 'Name', 'Amount', and 'ReasonId'. I want to sum the amount and put the reasons on one row to keep every name to a single line. There are about 50 distinct ReasonId's so I do not want to name the column the name of the ReasonId's. Instead, I would like to name the columns 'Reason1', 'Reason2', 'Reason3', and 'Reason4'. One single name can have up to 4 different reasons.
I have this:
Name Amount ReasonId
-------------------------
Bob $5 7
Bob $8 6
John $2 8
John $5 9
John $3 9
John $8 4
I want to produce the following:
Name Amount Reason1 Reason2 Reason3 Reason4
-----------------------------------------------------
Bob $13 7 6 NULL NULL
John $18 8 9 4 NULL
One way to do this is to use the dense_rank window function to number the rows, and then use conditional aggregation to put the reason in the correct columns.
I can't see anything that would give the specific order of the reason columns though, maybe there is some column missing that provides the order?
with cte as (
select
name,
reasonid,
amount,
dense_rank() over (partition by name order by reasonid) rn
from your_table
)
select
name,
sum(amount) amount,
max(case when rn = 1 then reasonid end) reason1,
max(case when rn = 2 then reasonid end) reason2,
max(case when rn = 3 then reasonid end) reason3,
max(case when rn = 4 then reasonid end) reason4
from cte
group by name
If you have some column that gives the order you want then change the order by clause used in the dense_rank function.
Sample SQL Fiddle (using PG as MSSQL seems to be offline).
The output from the query above would be:
| name | amount | reason1 | reason2 | reason3 | reason4 |
|------|--------|---------|---------|---------|---------|
| Bob | 13 | 6 | 7 | (null) | (null) |
| John | 18 | 4 | 8 | 9 | (null) |
You could also use a pivot to achieve this; if you know the columns you can enter them in the script, but if not, you can use dynamic sql (there are reasons why you might want to avoid the dynamic solution).
The advantage of this route is that you can enter the column list in a table and then changes to that table will result in changes to your output with change to the script involved. The disadvantages are all those associated with dynamic SQL.
In the interests of variation, here is a dynamic SQL solution using temp tables to hold your data, since a different possibility has been provided:
-- set up your data
CREATE TABLE #MyTab (Name VARCHAR(4), Amount INT, ReasonId INT)
CREATE TABLE #AllPossibleReasons (Id INT,Label VARCHAR(10))
INSERT #AllPossibleReasons
VALUES
(1,'Reason1')
,(2,'Reason2')
,(3,'Reason3')
,(4,'Reason4')
,(5,'Reason5')
,(6,'Reason6')
,(7,'Reason7')
,(8,'Reason8')
,(9,'Reason9')
INSERT #MyTab
VALUES
('Bob',7,7)
,('Bob',8,6)
,('John',2,8)
,('John',5,9)
,('John',3,9)
,('John',8,4)
-----------------------------------------------------------------------------
-- The actual query
DECLARE #ReasonList VARCHAR(MAX) = ''
DECLARE #SQL VARCHAR(MAX)
SELECT #ReasonList = #ReasonList + ',' + QUOTENAME(Label)
FROM #AllPossibleReasons
SET #ReasonList = SUBSTRING(#ReasonList,2,LEN(#ReasonList))
SET #SQL =
'SELECT Name,Value,' + #ReasonList + ' FROM
(SELECT
M.Name,SUM(Amount) AS This, Label, SUM(Total.Value) AS Value
FROM
#MyTab AS M
INNER JOIN #AllPossibleReasons AS Reason ON M.ReasonId = Reason.Id
INNER JOIN(SELECT T.Name, SUM(Amount)Value
FROM #MyTab T GROUP BY T.Name) AS Total ON M.Name = Total.Name
GROUP BY M.Name, Reason.Label) AS Up
PIVOT (SUM(THis) FOR Label IN (' + #ReasonList + ')) AS Pvt'
EXEC (#SQL)
DROP TABLE #AllPossibleReasons
DROP TABLE #MyTab
Working from the information in ListAGG in SQLSERVER, I came up with this somewhat ugly example:
with tbl1 as (
-- Set up initial data set
select 'Bob' name, 5 amount, 7 ReasonId
union all select 'Bob' , 3, 4
union all select 'Bob', 2, 1
union all select 'Brian', 8, 2
union all select 'Bob', 6, 4
union all select 'Brian', 1, 3
union all select 'Tim', 2, 2)
, TBL2 AS ( -- Add a blank to separate the concatenation
SELECT NAME
, AMOUNT
, CAST(ReasonId as varchar) + ' ' ReasonId from tbl1
)
select ta.name
, Total
, ReasonIds from (
(select distinct name, stuff((select distinct '' + t2.ReasonId from tbl2 t2
where t1.name = t2.name
for xml path(''), type).value('.','NVARCHAR(MAX)'),1,0,' ') ReasonIds from tbl2 t1) ta
inner join ( select name, sum(amount) Total from tbl1 group by name) tb on ta.name = tb.name) ;
This converts TBL1 to the following:
name Total ReasonIds
Bob 16 1 4 7
Brian 9 2 3
Tim 2 2
If I have a table which contains dates, eg (in year-month-day then time format):
2015-06-22 12:39:11.257
2015-06-22 15:44:46.790
2015-06-22 15:48:50.583
2015-06-23 08:25:50.060
2015-07-01 07:11:37.037
2015-07-07 13:40:11.997
2015-07-08 13:12:08.723
2015-07-08 13:12:13.900
2015-07-08 13:12:16.010
2015-07-10 12:29:59.777
2015-07-13 15:42:49.077
2015-07-13 15:47:48.670
2015-07-13 15:47:51.547
2015-07-14 08:11:53.023
2015-07-14 08:14:21.243
2015-07-14 08:16:49.410
2015-07-14 08:17:11.997
2015-07-14 09:58:28.840
2015-07-14 09:59:34.640
2015-07-15 15:39:39.993
2015-07-17 08:45:20.157
2015-07-24 14:00:00.487
2015-07-24 14:03:53.773
2015-07-24 14:12:41.717
2015-07-24 14:13:33.957
2015-07-24 14:15:40.953
2015-08-25 12:43:03.920
... is there a way (in SQL) that I can find the longest unbroken sequence of days. I just need the total number of days. So in the above, there are entries for 22nd June and 23rd of June, so the sequence there is 2 days. There's also entries for 13th July, 14th July, and 15th July; this is the longest sequence - 3 days. I don't care about the time portion, so an entry just before midnight, then an entry just after would count as 2 days.
So I want some SQL that can look at the table, and return the value 3 for the above.
No need for a cursor or any type of recursion to solve this. You can do this using a gaps and islands technique. This produces the desired output from your sample data.
with SomeDates as
(
select cast('2015-06-22 12:39:11.257' as datetime) as MyDate union all
select '2015-06-22 15:44:46.790' union all
select '2015-06-22 15:48:50.583' union all
select '2015-06-23 08:25:50.060' union all
select '2015-07-01 07:11:37.037' union all
select '2015-07-07 13:40:11.997' union all
select '2015-07-08 13:12:08.723' union all
select '2015-07-08 13:12:13.900' union all
select '2015-07-08 13:12:16.010' union all
select '2015-07-10 12:29:59.777' union all
select '2015-07-13 15:42:49.077' union all
select '2015-07-13 15:47:48.670' union all
select '2015-07-13 15:47:51.547' union all
select '2015-07-14 08:11:53.023' union all
select '2015-07-14 08:14:21.243' union all
select '2015-07-14 08:16:49.410' union all
select '2015-07-14 08:17:11.997' union all
select '2015-07-14 09:58:28.840' union all
select '2015-07-14 09:59:34.640' union all
select '2015-07-15 15:39:39.993' union all
select '2015-07-17 08:45:20.157' union all
select '2015-07-24 14:00:00.487' union all
select '2015-07-24 14:03:53.773' union all
select '2015-07-24 14:12:41.717' union all
select '2015-07-24 14:13:33.957' union all
select '2015-07-24 14:15:40.953' union all
select '2015-08-25 12:43:03.920'
)
, GroupedDates as
(
select cast(MyDate as DATE) as MyDate
, DATEADD(day, - ROW_NUMBER() over (Order by cast(MyDate as DATE)), cast(MyDate as DATE)) as DateGroup
from SomeDates
group by cast(MyDate as DATE)
)
, SortedDates as
(
select DATEDIFF(day, min(MyDate), MAX(MyDate)) + 1 as GroupCount
, min(MyDate) as StartDate
, MAX(MyDate) as EndDate
from GroupedDates
group by DateGroup
)
select top 1 GroupCount
, StartDate
, EndDate
from SortedDates
order by GroupCount desc
The input here is, in fact:
select trunc(date_column,'DD') day
from your_table
group by trunc(date_column,'DD');
From this point I can consider dates as numbers to input more easier the data and your problem is to find longest consecutive sequence.
so, an input table:
create table a(
col integer);
insert into a values (1);
insert into a values (2);
insert into a values (4);
insert into a values (5);
insert into a values (6);
insert into a values (8);
insert into a values (9);
insert into a values (11);
insert into a values (13);
insert into a values (14);
insert into a values (17);
and with this query you will get the longest sequence starting from every line:
with s(col, i) as (
select col, 1 i from a
union all
select a.col, i + 1
from s join a on s.col = a.col+1
)
--select * from s
select col, max(i)
from s
group by col
order by col
;
Result:
col max
1 2
2 1
4 3
5 2
6 1
8 2
9 1
11 1
13 2
14 1
17 1
From this point you can easily select the maximum. Also, for dates you can use dateadd(dd,1,date_column).
The explanation of recursive CTE: For every row I will find (if exists) the next row and increment the column i. The recursion exits when there are no "next" line.
OBS: I believe the code can be improved, but you got the ideea.
SQLFIDDLE
UPDATE To improve performance and keep using recursivity we can start only from numbers that doesn't have a prior consecutive number.
with p as (
select * from (
select col, coalesce(col - (lag(col) over (order by col)),2) as has_prev
from a
) b
where has_prev != 1
),
s(col, i) as (
select col, 1 i from p
union all
select s.col, i + 1
from s join a on s.col+i = a.col
)
--select * from p
select col, max(i)
from s
group by col
order by col
;
SQLFIDDLE2
I have a result set from SELECT Statement, how can i split one column without any delimiter
this is my result
Size TCount TDevice
2 5 E01
4.5 3 W02E01
I want to have this
Size TCount TDevice
2 5 E
2 5 0
2 5 1
4.5 3 W
4.5 6 0 (we have 2 times of 0)
4.5 3 2
4.5 3 1
thank you
You can join onto an auxiliary numbers table. I am using spt_values for demo purposes but you should create a permanent one.
WITH Nums
AS (SELECT number
FROM master..spt_values
WHERE type = 'P'
AND number BETWEEN 1 AND 1000),
Result(Size, TCount, TDevice)
AS (SELECT 2, 5,'E01'
UNION ALL
SELECT 4.5,3,'W02E01')
SELECT Size,
COUNT(*) * TCount AS TCount,
SUBSTRING(TDevice, number, 1) AS TDevice
FROM Result
JOIN Nums
ON Nums.number <= LEN(TDevice)
GROUP BY Size,
TCount,
SUBSTRING(TDevice, number, 1)
;with cte as
(
select Size,TCount,
substring(TDevice, 1, 1) as Chars,
stuff(TDevice, 1, 1, '') as TDevice
from t1
union all
select Size,TCount,
substring(TDevice, 1, 1) as Chars,
stuff(TDevice, 1, 1, '') as TDevice
from cte
where len(TDevice) > 0
)
select distinct Size,sum(TCount),Chars
from cte
group by Size,Chars
SQL Fiddle
Advantage: It doesn't require any User defined function (UDF) to be created.