I have a table which store records of all dates of a month. I want to retrieve some data from it. The table is so large that I should only selecting a fews of them. If the records have a column "ric_date" which is a date, how can I select records from each of the dates in a month, while selecting only a fews from each date?
The table is so large that the records for 1 date can have 100000 records.
WITH T AS (
SELECT ric_date
FROM yourTable
WHERE rice_date BETWEEN #start_date AND #end_date -- thanks Aaron Bertrand
GROUP BY ric_date
)
SELECT CA.*
FROM T
CROSS APPLY (
SELECT TOP 500 * -- 'a fews'
FROM yourTable AS YT
WHERE YT.ric_date = T.ric_date
ORDER BY someAttribute -- not required, but useful
) AS CA
Rough idea. This will get the first three rows per day for the current month (or as many that exist for any given day - there may be days with no rows represented).
DECLARE
#manys INT = 3,
#month DATE = DATEADD(DAY, 1-DAY(GETDATE()), DATEDIFF(DAY, 0, GETDATE()));
;WITH x AS
(
SELECT some_column, ric_date, rn = ROW_NUMBER() OVER
(PARTITION BY ric_date ORDER BY ric_date)
FROM dbo.data
WHERE ric_date >= #month
AND ric_date < DATEADD(MONTH, 1, #month)
)
SELECT some_column, ric_date FROM x
WHERE rn <= #manys;
If you don't have supporting indexes (most importantly on ric_date), this won't necessarily scale well at the high end.
Related
I wrote a recursive query to generate a column pf dates. I want the dates to be stored as a table in a db but can't seem to find a way.
declare #startdate date = '2014-01-01';
declare #enddate date = '2023-12-31';
with calendar as
(
select #startdate as [orderDate]
union all
select DATEADD(dd,1,[orderdate])
from calendar
where DATEADD(dd,1,[orderdate])<= #enddate
)
select * from calendar
option (maxrecursion 0);
you can try this one to fill a new table your_table with the dates.
You can use that as a basis for your further operations.
WITH x AS (SELECT n FROM (VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) v(n))
select
convert(date, dat ) Dat
into your_table
from
(
SELECT top 100 percent
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) Line,
dateadd(day, ROW_NUMBER() OVER (ORDER BY (SELECT NULL)), '2014-01-01') Dat
FROM x ones, x tens, x hundreds, x thousands
ORDER BY 1
) basis
where dat <= '2023-12-31'
I have a T-SQL Quotes table and need to be able to count how many quotes were in an open status during past months.
The dates I have to work with are an 'Add_Date' timestamp and an 'Update_Date' timestamp. Once a quote is put into a 'Closed_Status' of '1' it can no longer be updated. Therefore, the 'Update_Date' effectively becomes the Closed_Status timestamp.
I'm stuck because I can't figure out how to select all open quotes that were open in a particular month.
Here's a few example records:
Quote_No Add_Date Update_Date Open_Status Closed_Status
001 01-01-2016 NULL 1 0
002 01-01-2016 3-1-2016 0 1
003 01-01-2016 4-1-2016 0 1
The desired result would be:
Year Month Open_Quote_Count
2016 01 3
2016 02 3
2016 03 2
2016 04 1
I've hit a mental wall on this one, I've tried to do some case when filtering but I just can't seem to figure this puzzle out. Ideally I wouldn't be hard-coding in dates because this spans years and I don't want to maintain this once written.
Thank you in advance for your help.
You are doing this by month. So, three options come to mind:
A list of all months using left join.
A recursive CTE.
A number table.
Let me show the last:
with n as (
select row_number() over (order by (select null)) - 1 as n
from master..spt_values
)
select format(dateadd(month, n.n, q.add_date), 'yyyy-MM') as yyyymm,
count(*) as Open_Quote_Count
from quotes q join
n
on (closed_status = 1 and dateadd(month, n.n, q.add_date) <= q.update_date) or
(closed_status = 0 and dateadd(month, n.n, q.add_date) <= getdate())
group by format(dateadd(month, n.n, q.add_date), 'yyyy-MM')
order by yyyymm;
This does assume that each month has at least one open record. That seems reasonable for this purpose.
You can use datepart to extract parts of a date, so something like:
select datepart(year, add_date) as 'year',
datepart(month, date_date) as 'month',
count(1)
from theTable
where open_status = 1
group by datepart(year, add_date), datepart(month, date_date)
Note: this counts for the starting month and primarily to show the use of datepart.
Updated as misunderstood the initial request.
Consider following test data:
DECLARE #test TABLE
(
Quote_No VARCHAR(3),
Add_Date DATE,
Update_Date DATE,
Open_Status INT,
Closed_Status INT
)
INSERT INTO #test (Quote_No, Add_Date, Update_Date, Open_Status, Closed_Status)
VALUES ('001', '20160101', NULL, 1, 0)
, ('002', '20160101', '20160301', 0, 1)
, ('003', '20160101', '20160401', 0, 1)
Here is a recursive solution, that doesn't rely on system tables BUT also performs poorer. As we are talking about months and year combinations, the number of recursions will not get overhand.
;WITH YearMonths AS
(
SELECT YEAR(MIN(Add_Date)) AS [Year]
, MONTH(MIN(Add_Date)) AS [Month]
, MIN(Add_Date) AS YMDate
FROM #test
UNION ALL
SELECT YEAR(DATEADD(MONTH,1,YMDate))
, MONTH(DATEADD(MONTH,1,YMDate))
, DATEADD(MONTH,1,YMDate)
FROM YearMonths
WHERE YMDate <= SYSDATETIME()
)
SELECT [Year]
, [Month]
, COUNT(*) AS Open_Quote_Count
FROM YearMonths ym
INNER JOIN #test t
ON (
[Year] * 100 + [Month] <= CAST(FORMAT(t.Update_Date, 'yyyyMM') AS INT)
AND t.Closed_Status = 1
)
OR (
[Year] * 100 + [Month] <= CAST(FORMAT(SYSDATETIME(), 'yyyyMM') AS INT)
AND t.Closed_Status = 0
)
GROUP BY [Year], [Month]
ORDER BY [Year], [Month]
Statement is longer, also more readable and lists all year/month combinations to date.
Take a look at Date and Time Data Types and Functions for SQL-Server 2008+
and Recursive Queries Using Common Table Expressions
I have following SQL statement:
declare #dateFrom datetime = '2015-01-01';
declare #dateTo datetime = '2015-12-31';
select
DATEPART(WEEK, OrderDate) Week, Count(*) Number
from
table
where
OrderDate between #dateFrom and #dateTo
group by
DATEPART(WEEK, OrderDate)
order by
Week
It returns the number of orders per week, but if there were no orders at all this respective week is omitted.
How can I change the statement so it will also include weeks with 0 orders?
Gofr1 was on the right track but there are issues with the query.
1 - You do not want to use the datediff() of the begin and end as the stopping condition. It works for a whole year but will not work for partial ranges.
2 - I would add year to the key since that will allow you to handle cross year cases.
3 - You need to roll up the sales before using the Year Week Common Table Expression. Otherwise you just toss out the nulls again (order dates) with the WHERE clause.
Remember, logically the join is applied then the where clause.
The code below uses the Adventure Works 2012 DW database and obtains the correct answer.
Uses a tally table for some numbers.
Generates weekly dates and calculates year/week key for given range.
Rolls up sales from the fact table for given range.
Left joins the keys to the sales and turns null totals to zero.
Code:
-- Declare start and end date
DECLARE #dte_From datetime = '2005-07-01';
DECLARE #dte_To datetime = '2007-12-31';
-- About 200K numbers
WITH cte_Tally (n) as
(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL))
FROM sys.all_views a
CROSS JOIN sys.all_views b
),
-- Create year/week key
cte_YearWeekKey (MyKey) as
(
SELECT
year(dateadd(week, t.n, #dte_from)) * 1000 +
datepart(week, dateadd(week, t.n, #dte_from)) as MyKey
FROM
cte_Tally as t
WHERE
dateadd(week, t.n, #dte_from) < #dte_To
),
-- Must roll up here
cte_Sales (MyKey, MyTotal) as
(
SELECT
YEAR(F.OrderDate) * 1000 +
DATEPART(WEEK, F.OrderDate) as MyKey,
COUNT(*) as MyTotal
FROM
[AdventureWorksDW2012].[dbo].[FactResellerSales] F
WHERE
F.OrderDate between #dte_From and #dte_To
GROUP BY
YEAR(F.OrderDate) * 1000 +
DATEPART(WEEK, F.OrderDate)
)
-- Join the results
SELECT
K.MyKey, ISNULL(S.MyTotal, 0) as Total
FROM
cte_YearWeekKey as K
LEFT JOIN
cte_Sales as S
ON
k.MyKey = S.MyKey
My table creates a new record with timestamp daily when an integration is successful. I am trying to create a query that would check (preferably automated) the number of days in a month vs number of records in the table within a time frame.
For example, January has 31 days, so i would like to know how many days in january my process was not successful. If the number of records is less than 31, than i know the job failed 31 - x times.
I tried the following but was not getting very far:
SELECT COUNT (DISTINCT CompleteDate)
FROM table
WHERE CompleteDate BETWEEN '01/01/2015' AND '01/31/2015'
Every 7 days the system executes the job twice, so i get two records on the same day, but i am trying to determine the number of days that nothing happened (failures), so i assume some truncation of the date field is needed?!
One way to do this is to use a calendar/date table as the main source of dates in the range and left join with that and count the number of null values.
In absence of a proper date table you can generate a range of dates using a number sequence like the one found in the master..spt_values table:
select count(*) failed
from (
select dateadd(day, number, '2015-01-01') date
from master..spt_values where type='P' and number < 365
) a
left join your_table b on a.date = b.CompleteDate
where b.CompleteDate is null
and a.date BETWEEN '01/01/2015' AND '01/31/2015'
Sample SQL Fiddle (with count grouped by month)
Assuming you have an Integers table*. This query will pull all dates where no record is found in the target table:
declare #StartDate datetime = '01/01/2013',
#EndDate datetime = '12/31/2013'
;with d as (
select *, date = dateadd(d, i - 1 , #StartDate)
from dbo.Integers
where i <= datediff(d, #StartDate, #EndDate) + 1
)
select d.date
from d
where not exists (
select 1 from <target> t
where DATEADD(dd, DATEDIFF(dd, 0, t.<timestamp>), 0) = DATEADD(dd, DATEDIFF(dd, 0, d.date), 0)
)
Between is not safe here
SELECT 31 - count(distinct(convert(date, CompleteDate)))
FROM table
WHERE CompleteDate >= '01/01/2015' AND CompleteDate < '02/01/2015'
You can use the following query:
SELECT DATEDIFF(day, t.d, dateadd(month, 1, t.d)) - COUNT(DISTINCT CompleteDate)
FROM mytable
CROSS APPLY (SELECT CAST(YEAR(CompleteDate) AS VARCHAR(4)) +
RIGHT('0' + CAST(MONTH(CompleteDate) AS VARCHAR(2)), 2) +
'01') t(d)
GROUP BY t.d
SQL Fiddle Demo
Explanation:
The value CROSS APPLY-ied, i.e. t.d, is the ANSI string of the first day of the month of CompleteDate, e.g. '20150101' for 12/01/2015, or 18/01/2015.
DATEDIFF uses the above mentioned value, i.e. t.d, in order to calculate the number of days of the month that CompleteDate belongs to.
GROUP BY essentially groups by (Year, Month), hence COUNT(DISTINCT CompleteDate) returns the number of distinct records per month.
The values returned by the query are the differences of [2] - 1, i.e. the number of failures per month, for each (Year, Month) of your initial data.
If you want to query a specific Year, Month then just simply add a WHERE clause to the above:
WHERE YEAR(CompleteDate) = 2015 AND MONTH(CompleteDate) = 1
SQL Server 2005
I have an SQL Function (ftn_GetExampleTable) which returns a table with multiple result rows
EXAMPLE
ID MemberID MemberGroupID Result1 Result2 Result3 Year Week
1 1 1 High Risk 2 xx 2011 22
2 11 4 Low Risk 1 yy 2011 21
3 12 5 Med Risk 3 zz 2011 25
etc.
Now I do a count and group by on a table above this for Result 2 for instance so I get
SELECT MemberGroupID, Result2, Count(*) AS ExampleCount, Year, Week
FROM ftn_GetExampleTable
GROUP BY MemberGroupID, Result2, Year, Week
MemberGroupID Result2 ExampleCount Year Week
1 2 4 2011 22
4 1 2 2011 21
5 3 1 2011 25
Now imagine when I go to graph this new table between Weeks 20 and 23 of Year 2011, you'll see that it won't graph 20 or 23 or certain groups or even certain results in this example as they are not in the included data, so I need "false data" inserted into this table which has all the possibilities so they at least show on a graph even if the count is 0, does this make sense?
I am wondering on the easiest and kind of most dynamic way as it could be Result1 or Result3 I want to Graph on (different column types).
Thanks in advance
It looks like your dimensions are: MemberGroupID,Result2, and week (Year,Week).
One approach to solving this is to generate a list of all values you want for all the dimensions, and produce a cartesian product of them. As an example,
SELECT m.MemberGroupID, n.Result2, w.Year, w.Week
FROM (SELECT MemberGroupID FROM ftn_GetExampleTable GROUP BY MemberGroupID) m
CROSS
JOIN (SELECT Result2 FROM ftn_GetExampleTable GROUP BY Result2 ) n
CROSS
JOIN (SELECT Year, Week FROM myCalendar WHERE ... ) w
You don't necessarily need a table named myCalendar. (That approach does seem to be the popular one.) You just need a row source from which you can derive a list of (Year, Week) tuples. (There are answers to the question elsewhere in Stackoverflow, how to generate a list of dates.)
And the list of MemberGroupID and Result2 values doesn't have to come from the ftn_GetExampleTable rowsource, you could substitute another query.
With a cartesian product of those dimensions, you've got a complete "grid". Now you can LEFT JOIN your original result set to that.
Any place you don't have a matching row from the "gappy" result query, you'll get a NULL returned. You can leave the NULL, or replace it with a 0, which is probably what you want if it's a "count" you are returning.
SELECT d.MemberGroupID
, d.Result2
, d.Year
, d.Week
, IFNULL(r.ExampleCount,0) as ExampleCount
FROM ( <dimension query from above> ) d
LEFT
JOIN ( <original ExampleCount query> ) r
ON r.MemberGroupID = d.MemberGroupID
AND r.Result2 = d.Result2
AND r.Year = d.Year
AND r.Week = d.Week
That query can be refactored to make use of Common Table Expressions, which makes the query a little easier to read, especially if you are including multiple measures.
; WITH d AS ( /* <dimension query with no gaps (example above)> */
)
, r AS ( /* <original query with gaps> */
SELECT MemberGroupID, Result2, Count(*) AS ExampleCount, Year, Week
FROM ftn_GetExampleTable
GROUP BY MemberGroupID, Result2, Year, Week
)
SELECT d.*
, IFNULL(r.ExampleCount,0)
FROM d
LEFT
JOIN r
ON r.Year=d.Year AND r.Week=d.Week AND r.MemberGroupID = d.MemberGroupID
AND r.Result2 = d.Result2
This isn't a complete working solution to your problem, but it outlines an approach you can use.
Whenever I need to generate a sequence within SQL-Server I use the sys.all_objects table along with the ROW_NUMBER function, then maninpulate it as required:
SELECT ROW_NUMBER() OVER(ORDER BY Object_ID) AS Sequence
FROM Sys.All_Objects
So for the list of year and week numbers I would use:
DECLARE #StartDate DATETIME,
#EndDate DATETIME
SET #StartDate = '20110101'
SET #EndDate = '20120601'
SELECT DATEPART(YEAR, Date) AS YEAR,
DATEPART(WEEK, Date) AS WeekNum
FROM ( SELECT DATEADD(WEEK, ROW_NUMBER() OVER(ORDER BY Object_ID) - 1, #StartDate) AS Date
FROM Sys.All_Objects
) Dates
WHERE Date < #endDate
Where the dates subquery provides a list of dates at one week intervals between your start and end dates.
So in your example the end result would be something like:
DECLARE #StartDate DATETIME,
#EndDate DATETIME
SET #StartDate = '20110101'
SET #EndDate = '20120601'
;WITH Data AS
( SELECT MemberGroupID,
Result2,
Count(*) AS ExampleCount,
Year,
Week
FROM ftn_GetExampleTable
GROUP BY MemberGroupID, Result2, Year, Week
), Dates AS
( SELECT DATEPART(YEAR, Date) AS YEAR,
DATEPART(WEEK, Date) AS WeekNum
FROM ( SELECT DATEADD(WEEK, ROW_NUMBER() OVER(ORDER BY Object_ID) - 1, #StartDate) AS Date
FROM Sys.All_Objects
) Dates
WHERE Date < #endDate
)
SELECT YearNum,
WeeNum,
MemberID,
Result2,
COALESCE(ExampleCount, 0) AS ExampleCount
FROM Dates
LEFT JOIN Data
ON YearNum = Data.Year
AND WeekNum = Data.Week