I have a query that has InsertDate and flag field. I need to set the flag to Y for the first 10 minutes, and every 12 hours after that. This is what I have so far, but hard-coded is not an ideal at all.
select InsertDate, case when DATEDIFF(MINUTE, MAX(InsertDate),
GETDATE()) <= 10 then 'Y' when DATEDIFF(MINUTE, MAX(InsertDate),
GETDATE()) = 720 then 'Y' when DATEDIFF(MINUTE, MAX(InsertDate),
GETDATE()) = 1440 then 'Y' Else 'N' end as flag
How do I update my syntax to get away from hard-coded? Thank you for any helps
Your query is not valid SQL to start with: it has no from clause, and having both insertdate and max(insertdate) in the select clause makes no sense.
Bottom line, I think you want modulo artithmetics:
case
when datediff(minute, insertdate, getdate()) <= 10 then 'y'
when datediff(minute, insertdate, getdate()) % 720 = 0 then 'y'
else 'n'
end as flag
<expr> % 720 = 0 reads as: <expr> is a multiple of 720.
Related
I tried to use the result of a SELECT inside of the IN operator of another SELECT but it takes 15 minutes, but if I run the queries(Query1 and Query 2 below) separate I have results in 2 minutes approximate
I tried to use the result of a SELECT inside of the IN clause of another SELECT but it's really slow
Query 1 takes 1 minute
SELECT Id_A
FROM [Database]..[Table_A]
WHERE location = 'US'
AND datetime_in >= DATEADD(DAY,-30,GETDATE())
AND (
CASE WHEN date_sent IS NULL THEN DATEDIFF(hh, datetime_in, GETDATE())
WHEN date_sent IS NOT NULL THEN DATEDIFF(hh, datetime_in, ship_date)
ELSE 0 END) > 120
Query 2 takes 10 seconds
SELECT *
FROM [Database]..[Table_B]
WHERE Id_B IN (HERE I INSERT MANUALLY ALL THE Table_A..Id_A)
Query 3 taking more then 15 minutes this is the one giving me issues
SELECT *
FROM [Database]..[Table_B]
WHERE Id_B IN (SELECT Id_A
FROM [Database]..[Table_A]
WHERE location = 'US'
AND datetime_in >= DATEADD(DAY,-30,GETDATE())
AND (CASE WHEN date_sent IS NULL
THEN DATEDIFF(hh, datetime_in, GETDATE())
WHEN date_sent IS NOT NULL
THEN DATEDIFF(hh, datetime_in, ship_date)
ELSE 0 END) > 120)
I am trying to optimize so the query 3 can be executed and give results in less then 5 minutes maybe?
Depending on how much data you're working with, utilising temporary tables and indices on those tables may be the most optimal approach. It's a technique I tend to use regularly when I work with databases with insufficient indices, or where correlated subqueries are expensive:
DROP TABLE IF EXISTS #ids;
SELECT Id_A
INTO #ids
FROM [Database]..[Table_A]
WHERE location = 'US'
AND datetime_in >= DATEADD(DAY,-30,GETDATE())
AND (
CASE WHEN date_sent IS NULL THEN DATEDIFF(hh, datetime_in, GETDATE())
WHEN date_sent IS NOT NULL THEN DATEDIFF(hh, datetime_in, ship_date)
ELSE 0 END
) > 120;
CREATE INDEX [IX_ids] ON #ids(Id_A);
SELECT *
FROM [Database]..[Table_B]
WHERE EXISTS (
SELECT * FROM #ids WHERE Id_A = Id_B
);
It looks like your are just trying to do a JOIN. Why not trying to make it simple, it will be MUCH faster that way:
SELECT TB.*
FROM [Database]..[Table_B] AS TB
JOIN [Database]..[Table_A] AS TA
ON TB.Id_B = TA.Id_A
WHERE TA.location = 'US'
AND TA.datetime_in >= DATEADD(DAY,-30,GETDATE())
AND (CASE WHEN TA.date_sent IS NULL THEN DATEDIFF(hh, TA.datetime_in, GETDATE())
WHEN TA.date_sent IS NOT NULL THEN DATEDIFF(hh, TA.datetime_in, TA.ship_date)
ELSE 0 END) > 120)
I may be missing something obvious! Thanks in advance for any help.
I am trying to use a CASE statement in an inline SQL Statement. I only want to evaluate the expression once, so I am looking to put the expression in the CASE section, and then evaluate the result in each WHEN. Here is the example:
SELECT
MyTable.ColumnA,
CASE DateDiff(d, MyTable.MyDate, getDate())
WHEN <= 0 THEN 'bad'
WHEN BETWEEN 1 AND 15 THEN 'reasonable'
ELSE 'good'
END as MyCalculatedColumn,
MyTable.SomeOtherColumn
I know I can do this:
CASE
WHEN DateDiff(d, MyTable.MyDate, getDate()) <= 0 THEN 'bad'
WHEN DateDiff(d, MyTable.MyDate, getDate()) BETWEEN 1 AND 15 THEN 'reasonable'
ELSE 'good'
END
But in my first example, SQL does not seem to like this statement:
WHEN <= 0 THEN 'bad'
Note that the statement is inline with other SQL, so I can't do something like:
DECLARE #DaysDiff bigint
SET #DaysDiff = DateDiff(d, MyTable.MyDate, getDate())
CASE #DaysDiff
WHEN <= 0 THEN 'bad'
WHEN BETWEEN 1 AND 15 THEN 'reasonable'
ELSE 'good'
END
My actual DateDiff expression is much more complex and I only want to maintain its logic, and have it evaluated, only once.
Thanks again...
You can use apply for this purpose:
SELECT MyTable.ColumnA,
(CASE WHEN day_diff <= 0 THEN 'bad'
WHEN BETWEEN 1 AND 15 THEN 'reasonable'
ELSE 'good'
END) as MyCalculatedColumn,
MyTable.SomeOtherColumn
FROM MyTable CROSS APPLY
(VALUES (DateDiff(day, MyTable.MyDate, getDate()))) v(day_diff)
APPLY is a very handy way to add calculated values into a statement. Because they are defined in the FROM clause, they can be used in SELECT, WHERE, and GROUP BY clauses where column aliases would not be recognized.
I see your problem. CASE expression WHEN value can only do an equality check
You could try using a CTE (Common Table Expression), do everything except the case statement in the CTE and then put the CASE in the final SELECT at the end. I'm not sure whether it will prevent the expression being evaluated twice - thats kindof the optimisers problem, not yours (thats how I like to think about it)
WITH cteMyComplexThing AS(
SELECT MyTable.ColumnA,
DateDiff(d, MyTable.MyDate, getDate()) as ComplexThing,
MyTable.SomeOtherColumn
FROM MyTable
)
SELECT
ColumnA,
CASE
WHEN ComplexThing <= 0 THEN 'bad'
WHEN ComplexThing BETWEEN 1 AND 15 THEN 'reasonable'
ELSE 'good'
END as MyCalculatedColumn,
SomeOtherColumn
FROM cteMyComplexThing
The WHEN clause in a CASE statement needs both sides of the condition. <=0 cannot stand by itself.
CASE #DaysDiff
WHEN ? <= 0 THEN 'bad'
WHEN BETWEEN 1 AND 15 THEN 'reasonable'
ELSE 'good'
END
Below is my current SQL Server 2012 query. Basically I want the information from the last business day, but on Monday, I want it to pull Friday's info instead of Sunday. This is what I have so far in my query but it won't accept it.
USE [LetterGeneration]
SELECT
g.LetterGenerationPrintJobId,
CONVERT(CHAR(12), r.CreatedDate, 101) AS CreatedDate,
YEAR(r.CreatedDate) AS Year,
MONTH(r.CreatedDate) AS Month,
DAY(r.CreatedDate) AS Day,
CASE
WHEN DATEPART(dw, r.CreatedDate) = 1
THEN 1
WHEN DATEPART(dw, r.CreatedDate) = 7
THEN 1
ElSE 0
END AS Weekend,
s.LetterGenerationStatusId AS Status,
COUNT(g.LetterGenerationId) AS LetterCount,
SUM(g.LetterPageCount) AS PageCount,
t.IsLitigationCoverLetterAllowed,
CASE
WHEN g.CarrierTrackingNumber LIKE '%1ZE%'
THEN 1
WHEN g.CarrierTrackingNumber LIKE '921489%'
THEN 2
WHEN g.CarrierTrackingNumber LIKE '917190%'
THEN 2
ELSE 3
END AS CarrierType
FROM
[LetterGenerationTemplateRequest] AS R
INNER JOIN
[LetterGenerationTemplate] AS T ON t.[LetterGenerationTemplateId] = r.LetterGenerationTemplateId
INNER JOIN
LetterGeneration G ON g.LetterGenerationTemplateRequestId = r.LetterGenerationTemplateRequestId
INNER JOIN
LetterGenerationStatus S ON g.LetterGenerationStatusId = s.LetterGenerationStatusId
WHERE
(CASE
WHEN (DATENAME(dw,GETDATE()) = 'Monday')
THEN (DATEDIFF(d, r.CreatedDate, GETDATE()) = 3)
ELSE (DATEDIFF(d, r.CreatedDate, GETDATE()) = 1)
END)
AND t.[TemplateKey] NOT LIKE '%PLTV1%'
AND s.LetterGenerationStatusId = 19
ORDER BY
r.CreatedDate DESC, g.LetterGenerationPrintJobId DESC
What am I missing or misunderstanding about my WHERE clause in order to make it work in the way I'm thinking?
Thanks
Maybe convert to a regular AND/OR?
WHERE (
((DATENAME(dw,GETDATE()) = 'Monday') AND (DATEDIFF(d, r.CreatedDate, GETDATE()) = 3))
OR
(DATEDIFF(d, r.CreatedDate, GETDATE()) = 1)
)
....
What am I missing or misunderstanding about my WHERE clause in order to make it work in the way I'm thinking?
Though you haven't given the error message you're getting, I'm sure it's syntax related because you're putting the test INSIDE the result of the case, not outside it
You're writing:
WHERE CASE WHEN it_is_monday THEN data_date = friday ELSE data_date = yesterday END
You should be writing:
WHERE data_date = CASE WHEN it_is_monday THEN friday ELSE yesterday END
Essentially: you're not supposed to use case/when in a where clause to do your "column = something" comparison and return you true or false, you're supposed to use it to just return the "something" you compare against "column" else in order to get your true or false
The other answers focus on "giving you a working solution"; this answer focuses on telling you what was going wrong with your thought processes re your original query
Here's a simpler example:
--wrong syntax to search a table full of cats (4 legs) and people (2 legs)
WHERE CASE WHEN animal_type = 'cat' THEN legs = 4 ELSE legs = 2 END
--right syntax
WHERE limbs = CASE WHEN animal_type = 'cat' THEN 4 ELSE 2 END
Ignoring holidays for a second, and assuming you have at least one record for every date, something like this should work.
where cast(createdDate as date) =
(select max(createdDate )
from table
where createdDate < cast(getDate() as date
and dateName(dw, createdDate in ('Monday' etc)
)
In order to maintain SARGability(able to do a seek against an index) you want to make sure the table columns in the predicate aren't included in any functions.
The following should work and maintain SARGability...
WHERE
r.CreatedDate = CASE
WHEN DATEPART(dw, getdate) = 2
THEN DATEADD(dd, -3, CAST(GETDATE() AS DATE))
ELSE CAST(GETDATE() AS DATE)
END
HTH,
Jason
I have a query like so:
SELECT Col1, Col2, Col3, ColDate
FROM TableA
WHERE DAY(ColDate) = 1
AND MONTH(ColDate) = MONTH(CASE WHEN DATEPART(HOUR, GETDATE()) < 16 THEN GETDATE() - 1 ELSE GETDATE()END)
AND YEAR(ColDate) = YEAR(CASE WHEN DATEPART(HOUR, GETDATE()) < 16 THEN GETDATE() - 1 ELSE GETDATE()END)
The query above pulls data daily into another table. Now, the issue with this query is that we have to manually change the DAY(ColDate) =? in the WHERE Clause everyday to pull the right data. How do I set my WHERE Clause to check the day in that month and pull data accordingly?
Is this what you are looking for?
WHERE DAY(colDate) = DAY(GETDATE()) AND
. . .
Or, perhaps:
WHERE DAY(colDate) = DAY(CASE WHEN DATEPART(HOUR, GETDATE()) < 16 THEN GETDATE() - 1 ELSE GETDATE() END) AND
I'm trying to show a log of daily transactions that take place. My current method is embarrassingly inefficient and I'm sure there is a much better solution. Here is my current query:
select ReaderMACAddress,
count(typeid) as 'Total Transactions',
SUM(CASE WHEN CAST("Timestamp" as TIME) between '05:00:00' and '11:59:59' THEN 1 ELSE 0 END) as 'Morning(5am-12pm)',
SUM(CASE WHEN CAST("Timestamp" as TIME) between '12:00:00' and '17:59:59' THEN 1 ELSE 0 END) as 'AfternoonActivity(12pm-6pm)',
SUM(CASE WHEN CAST("Timestamp" as TIME) between '18:00:00' and '23:59:59' THEN 1 ELSE 0 END) as 'EveningActivity(6pm-12am)',
SUM(CASE WHEN CAST("Timestamp" as TIME) between '00:00:00' and '04:59:59' THEN 1 ELSE 0 END) as 'OtherActivity(12am-5am)'
from Transactions
where ReaderMACAddress = '0014f54033f5'
Group by ReaderMACAddress;
which returns the results:
ReaderMACAddress Total Transactions Morning(5am-12pm) AfternoonActivity(12pm-6pm) EveningActivity(6pm-12am) OtherActivity(12am-5am)
0014f54033f5 932 269 431 232 0
(sorry for any alignment issues here)
At the moment I only want to look at a single Reader that I specify (through the where clause). Ideally, it would be easier to read if the time sections were in a single column and the results, i.e. a count function were in a second column yielding results such as:
Total Transactions 932
Morning(5am-12pm) 269
AfternoonActivity(12pm-6pm) 431
EveningActivity(6pm-12am) 232
OtherActivity(12am-5am) 0
Thanks for any help :)
I would first consider a computed column, but I believe from a previous post you don't have the ability to change the schema. So how about a view?
CREATE VIEW dbo.GroupedReaderView
AS
SELECT ReaderMACAddress,
Slot = CASE WHEN t >= '05:00' AND t < '12:00' THEN 1
WHEN t >= '12:00' AND t < '18:00' THEN 2
WHEN t >= '18:00' THEN 3 ELSE 4 END
FROM
(
SELECT ReaderMACAddress, t = CONVERT(TIME, [Timestamp])
FROM dbo.Transactions
) AS x;
Now your per-MAC address query is much, much simpler:
SELECT Slot, COUNT(*)
FROM dbo.GroupedReaderView
WHERE ReaderMACAddress = '00...'
GROUP BY Slot;
This will provide a result like:
1 269
2 431
3 232
4 0
You can also add WITH ROLLUP which will provide a grand total with the Slot column being NULL:
SELECT Slot, COUNT(*)
FROM dbo.GroupedReaderView
WHERE ReaderMACAddress = '00...'
GROUP BY Slot
WITH ROLLUP;
Should yield:
1 269
2 431
3 232
4 0
NULL 932
And you can pivot that if you need to, add labels per slot, etc. in your presentation tier.
You could also do it this way, it just makes the view a lot more verbose and pulls a lot of extra data when you query it directly; it's also slightly less efficient to group by strings.
CREATE VIEW dbo.GroupedReaderView
AS
SELECT ReaderMACAddress,
Slot = CASE WHEN t >= '05:00' AND t < '12:00' THEN
'Morning(5am-12pm)'
WHEN t >= '12:00' AND t < '18:00' THEN
'Afternoon(12pm-6pm)'
WHEN t >= '18:00' THEN
'Evening(6pm-12am)'
ELSE
'Other(12am-5am)'
END
FROM
(
SELECT ReaderMACAddress, t = CONVERT(TIME, [Timestamp])
FROM dbo.Transactions
) AS x;
These aren't necessarily more efficient than what you've got, but they're less repetitive and easier on the eyes. :-)
Also if you don't want to (or can't) create a view, you can just put that into a subquery, e.g.
SELECT Slot, COUNT(*)
FROM
(
SELECT ReaderMACAddress,
Slot = CASE WHEN t >= '05:00' AND t < '12:00' THEN
'Morning(5am-12pm)'
WHEN t >= '12:00' AND t < '18:00' THEN
'Afternoon(12pm-6pm)'
WHEN t >= '18:00' THEN
'Evening(6pm-12am)'
ELSE
'Other(12am-5am)'
END
FROM
(
SELECT ReaderMACAddress, t = CONVERT(TIME, [Timestamp])
FROM dbo.Transactions
) AS x
) AS y
WHERE ReaderMACAddress = '00...'
GROUP BY Slot
WITH ROLLUP;
Just an alternative that still lets you use BETWEEN and may be even a little less verbose:
SELECT Slot, COUNT(*)
FROM
(
SELECT ReaderMACAddress,
Slot = CASE WHEN h BETWEEN 5 AND 11 THEN 'Morning(5am-12pm)'
WHEN h BETWEEN 12 AND 17 THEN 'Afternoon(12pm-6pm)'
WHEN h >= 18 THEN 'Evening(6pm-12am)'
ELSE 'Other(12am-5am)'
END
FROM
(
SELECT ReaderMACAddress, h = DATEPART(HOUR, [Timestamp])
FROM dbo.Transactions
) AS x
) AS y
WHERE ReaderMACAddress = '00...'
GROUP BY Slot
WITH ROLLUP;
UPDATE
To always include each slot even if there are no results for that slot:
;WITH slots(s, label, h1, h2) AS
(
SELECT 1, 'Morning(5am-12pm)' , 5, 11
UNION ALL SELECT 2, 'Afternoon(12pm-6pm)' , 12, 17
UNION ALL SELECT 3, 'Evening(6pm-12am)' , 18, 23
UNION ALL SELECT 4, 'Other(12am-5am)' , 0, 4
)
SELECT s.label, c = COALESCE(COUNT(y.ReaderMACAddress), 0)
FROM slots AS s
LEFT OUTER JOIN
(
SELECT ReaderMACAddress, h = DATEPART(HOUR, [Timestamp])
FROM dbo.Transactions
WHERE ReaderMACAddress = '00...'
) AS y
ON y.h BETWEEN s.h1 AND s.h2
GROUP BY s.label
WITH ROLLUP;
The key in all of these cases is to simplify and not repeat yourself. Even if SQL Server only performs it once, why convert to time 4+ times?