Displaying Date Overlaps from a single Table in T-SQL - tsql

I have the following Episode table example:
Please note, where DischDate= "2020-02-20" means - client hasn't been discharged.
It's like NULL (this date meant to fill out NULL)
My goal is do display all possible overlaps within the same EHRClientFK, as following:
See the schema of my all possible Overlaps:
So, in this table's case I expect to display -
EHRClientFK / AdmDate / DischDate for only EHRClientFK = 2, 4, 3, 5 (which satisfies the schema):
This should be the resulting table:
EHRClientFK values 8,9,10 have no duplicate (overlaps), Clients 6, 7 have two adm-disch dates, but they
are NOT overlapping betw. each other
To achieve this result, I have the following code:
SELECT
a.[EHRClientFK]
,a.[AdmDate]
,a.[DischDate]
FROM [WH].[dbo].[Episode] a
INNER JOIN [WH].[dbo].[Episode] b ON a.EHRClientFK = b.EHRClientFK
WHERE
((a.DischDate = '2020-02-20') AND (b.DischDate = '2020-02-20'))
OR ((a.AdmDate < b.DischDate) AND (b.AdmDate < a.DischDate))
GROUP BY
a.[EHRClientFK]
,a.[AdmDate]
,a.[DischDate]
HAVING COUNT (*) >1
But, when I apply this on my original Table (with over 20K records) - I am still having non duplicate
EHRClientFK, like 8,9,10 (very insignificant amount, but still); and some cases of 6,7 with NO overlapping dates
How should I change my Where clause in order to satisfy my Overlap schema (to cover all overlap cases)"?

Related

groupBy Id and get multiple records for multiple columns in scala

I have a spark dataframe as below.
val df = Seq(("a",1,1400),("a",1,1250),("a",2,1200),("a",4,1250),("a",4,1200),("a",4,1100),("b",2,2500),("b",2,1250),("b",2,500),("b",4,250),("b",4,200),("b",4,100),("b",4,100),("b",5,800)).
toDF("id","hierarchy","amount")
I am working in scala language to make use of this data frame and trying to get result as shown below.
val df = Seq(("a",1,1400),("a",4,1250),("a",4,1200),("a",4,1100),("b",2,2500),("b",2,1250),("b",4,250),("b",4,200),("b",4,100),("b",5,800)).
toDF("id","hierarchy","amount")
Rules: Grouped by id, if min(hierarchy)==1 then I take the row with the highest amount and then I go on to analyze hierarchy >= 4 and take 3 of each of them in descending order of the amount. On the other hand, if min(hierarchy)==2 then I take two rows with the highest amount and then I go on to analyze hierarchy >= 4 and take 3 of each of them in descending order of the amount. And so on for all the id's in the data.
Thanks for the suggestions..
You may use window functions to generate the criteria which you will filter upon eg
val results = df.withColumn("minh",min("hierarchy").over(Window.partitionBy("id")))
.withColumn("rnk",rank().over(Window.partitionBy("id").orderBy(col("amount").desc())))
.withColumn(
"rn4",
when(col("hierarchy")>=4, row_number().over(
Window.partitionBy("id",when(col("hierarchy")>=4,1).otherwise(0)).orderBy(col("amount").desc())
) ).otherwise(5)
)
.filter("rnk <= minh or rn4 <=3")
.select("id","hierarchy","amount")
NB. More verbose filter .filter("(rnk <= minh or rn4 <=3) and (minh in (1,2))")
Above temporary columns generated by window functions to assist in the filtering criteria are
minh : used to determine the minimum hierarchy for a group id and subsequently select the top minh number of columns from the group .
rnk used to determine the rows with the highest amount in each group
rn4 used to determine the rows with the highest amount in each group with hierarchy >=4

Tableau - Calculating average where date is less than value from another data source

I am trying to calculate the average of a column in Tableau, except the problem is I am trying to use a single date value (based on filter) from another data source to only calculate the average where the exam date is <= the filtered date value from the other source.
Note: Parameters will not work for me here, since new date values are being added constantly to the set.
I have tried many different approaches, but the simplest was trying to use a calculated field that pulls in the filtered exam date from the other data source.
It successfully can pull the filtered date, but the formula does not work as expected. 2 versions of the calculation are below:
IF DATE(ATTR([Exam Date])) <= DATE(ATTR([Averages (Tableau Test Scores)].[Updated])) THEN AVG([Raw Score]) END
IF DATEDIFF('day', DATE(ATTR([Exam Date])), DATE(ATTR([Averages (Tableau Test Scores)].[Updated]))) > 1 THEN AVG([Raw Score]) END
Basically, I am looking for the equivalent of this in SQL Server:
SELECT AVG([Raw Score]) WHERE ExamDate <= (Filtered Exam Date)
Below a workbook that shows an example of what I am trying to accomplish. Currently it returns all blanks, likely due to the many-to-one comparison I am trying to use in my calculation.
Any feedback is greatly appreciated!
Tableau Test Exam Workbook
I was able to solve this by using Custom SQL to join the tables together and calculate the average based on my conditions, to get the column results I wanted.
Would still be great to have this ability directly in Tableau, but whatever gets the job done.
Edit:
SELECT
[AcademicYear]
,[Discipline]
--Get the number of student takers
,COUNT([Id]) AS [Students (N)]
--Get the average of the Raw Score
,CAST(AVG(RawScore) AS DECIMAL(10,2)) AS [School Mean]
--Get the number of failures based on an "adjusted score" column
,COUNT([AdjustedScore] < 70 THEN 1 END) AS [School Failures]
--This is the column used as the cutoff point for including scores
,[Average_Update].[Updated]
FROM [dbo].[Average] [Average]
FULL OUTER JOIN [dbo].[Average_Update] [Average_Update] ON ([Average_Update].[Id] = [Average].UpdateDateId)
--The meat of joining data for accurate calculations
FULL OUTER JOIN (
SELECT DISTINCT S.[Id], S.[LastName], S.[FirstName], S.[ExamDate], S.[RawScoreStandard], S.[RawScorePercent], S.[AdjustedScore], S.[Subject], P.[Id] AS PeriodId
FROM [StudentScore] S
FULL OUTER JOIN
(
--Get only the 1st attempt
SELECT DISTINCT [NBOMEId], S2.[Subject], MIN([ExamDate]) AS ExamDate
FROM [StudentScore] S2
GROUP BY [NBOMEId],S2.[Subject]
) B
ON S.[NBOMEId] = B.[NBOMEId] AND S.[Subject] = B.[Subject] AND S.[ExamDate] = B.[ExamDate]
--Group in "Exam Periods" based on the list of periods w/ start & end dates in another table.
FULL OUTER JOIN [ExamPeriod] P
ON S.[ExamDate] = P.PeriodStart AND S.[ExamDate] <= P.PeriodEnd
WHERE S.[Subject] = B.[Subject]
GROUP BY P.[Id], S.[Subject], S.[ExamDate], S.[RawScoreStandard], S.[RawScorePercent], S.[AdjustedScore], S.[NBOMEId], S.[NBOMELastName], S.[NBOMEFirstName], S.[SecondYrTake]) [StudentScore]
ON
([StudentScore].PeriodId = [Average_Update].ExamPeriodId
AND [StudentScore].Subject = [Average].Subject
AND [StudentScore].[ExamDate] <= [Average_Update].[Updated])
--End meat
--Joins to pull in relevant data for normalized tables
FULL OUTER JOIN [dbo].[Student] [Student] ON ([StudentScore].[NBOMEId] = [Student].[NBOMEId])
INNER JOIN [dbo].[ExamPeriod] [ExamPeriod] ON ([Average_Update].ExamPeriodId = [ExamPeriod].[Id])
INNER JOIN [dbo].[AcademicYear] [AcademicYear] ON ([ExamPeriod].[AcademicYearId] = [AcademicYear].[Id])
--This will pull only the latest update entry for every academic year.
WHERE [Updated] IN (
SELECT DISTINCT MAX([Updated]) AS MaxDate
FROM [Average_Update]
GROUP BY[ExamPeriodId])
GROUP BY [AcademicYear].[AcademicYearText], [Average].[Subject], [Average_Update].[Updated],
ORDER BY [AcademicYear].[AcademicYearText], [Average_Update].[Updated], [Average].[Subject]
I couldn't download your file to test with your data, but try reversing the order of taking the average ie
average(IF DATE(ATTR([Exam Date])) <= DATE(ATTR([Averages (Tableau Test Scores)].[Updated]) then [Raw Score]) END)
as written, I believe you'll be averaging the data before returning it from the if statement, whereas you want to return the data, then average it.

filtering on a range of values in a db column with sqlalchemy orm

I have a postgresql database and in one particular table, with many rows. One column in this table, called data, is a float array, REAL[], and gets filled with an array of ~4500 elements. I want to access this table through some query via SQLAlchemy and the ORM.
How do I select all rows in the table where a subset of this column satisfies some condition, e.g.contains a range of values? Like I want to select all rows where the data contains values >= 10, or values between >=10 and <=20.
Can I do this with a straight session query like
rows = session.query(Table).filter(Table.data.(some conditional)).all()
where my conditional is something like "VALUES >= 10 and VALUES <= 20"?
Or do I need to define some special methods, or setup, when I'm defining my SQLAlchemy table class. For example, I have my table set up as
class Table(Base):
__tablename__ = 'table'
__table_args__ = {'autoload' : True, 'schema' : 'testdb', 'extend_existing':True}
data = deferred(Column(ARRAY(Float)))
def __repr__(self):
return '<Table (pk={0})>'.format(self.pk)
Ideally I'd like to set it up so I can just do simple filtering in my session.query calls. Is this possible? I'm not super familiar with the ORM, so maybe it is?
I've had a look at the ARRAY Comparator sqlalchemy docs but those only seem to work on exact values. My data is precise to 6 sigfigs, and I don't know the exact values ahead of time.
What's the best way to do this? Thanks.
EDIT:
Based on the below comment, here is the code I'm using in attempting to select all rows (out of 1000) that have data (from 1 column) >= 1.0. There should be 537 rows.
rows = session.query(datadb.Table).filter(datadb.Table.data.any(1.0,operator=operators.le)).all()
This gives the correct subset number. len(rows) = 537. However, I don't understand the logic of with this operator, where to select data >=1.0 , I use the le operator? Also, along those same lines, there should be 234 rows that have data between the values >=1.0 and <1.0, but this statement fails to give the correct subset..
rows = session.query(datadb.Table).filter(datadb.Table.data.any(1.0,operator=operators.le)).filter(datadb.Table.data.any(1.2,operator=operators.ge)).all()
* EDIT 2 *
Here's an example of my database Table with a few rows. pk is an integer, and data is a real[].
db datadb
schema Table
pk data
0 [0.0,0.0,0.5,0.3,1.3,1.9,0.3,0.0,0.0]
1 [0.1,0.0,1.0,0.7,1.1,1.5,1.2,0.3,1.4]
2 [0.0,0.6,0.4,0.3,1.6,1.7,0.4,1.3,0.0]
3 [0.0,0.1,0.2,0.4,1.0,1.1,1.2,0.9,0.0]
4 [0.0,0.0,0.5,0.3,0.2,0.1,0.7,0.3,0.1]
I have 5 rows, 4 of them have data with values >= 1.0, while just 2 have values in the range >= 1.0 and <= 1.2. The query I would do to grab the rows is in the first case
rows = session.query(datadb.Table).filter(datadb.Table.data.any(1.0,operator=operators.le)).all()
This should return the 4 rows, at pk=0,1,2,3. This query does what I expect. The second case
rows = session.query(datadb.Table).filter(datadb.Table.data.any(1.0,operator=operators.le)).filter(datadb.Table.data.any(1.2,operator=operators.ge)).all()
and should return the 2 rows at pk=1,3. However this query just returns the 4 rows from the first query. For the second query, I also tried
rows = session.query(datadb.Table).filter(datadb.Table.data.any(1.0,operator=operators.le),datadb.Table.data.any(1.2,operator=operators.ge)).all()
which also didn't work.
Please read documentation on ARRAY.Comparator, according to which you should be able to do the following:
rows = (session.query(Table)
.filter(Table.data.any(10, operator=operators.le))
.filter(Table.data.any(20, operator=operators.ge)
).all()
EDIT:
# combined filter does not work,
# but applying one or the other is still useful as it reduces the result set
q = (session.query(MyTable)
.filter(MyTable.data.any(1.0, operator=operators.le))
# .filter(MyTable.data.any(1.2, operator=operators.ge))
)
# filter in memory
items = [_row for _row in q.all()
if any(1.0 <= item <= 1.2 for item in _row.data)]
for item in items:
print(item)

T-SQL Query to process data in batches without breaking groups

I am using SQL 2008 and trying to process the data I have in a table in batches, however, there is a catch. The data is broken into groups and, as I do my processing, I have to make sure that a group will always be contained within a batch or, in other words, that the group will never be split across different batches. It's assumed that the batch size will always be much larger than the group size. Here is the setup to illustrate what I mean (the code is using Jeff Moden's data generation logic: http://www.sqlservercentral.com/articles/Data+Generation/87901)
DECLARE #NumberOfRows INT = 1000,
#StartValue INT = 1,
#EndValue INT = 500,
#Range INT
SET #Range = #EndValue - #StartValue + 1
IF OBJECT_ID('tempdb..#SomeTestTable','U') IS NOT NULL
DROP TABLE #SomeTestTable;
SELECT TOP (#NumberOfRows)
GroupID = ABS(CHECKSUM(NEWID())) % #Range + #StartValue
INTO #SomeTestTable
FROM sys.all_columns ac1
CROSS JOIN sys.all_columns ac2
This will create a table with about 435 groups of records containing between 1 and 7 records in each. Now, let's say I want to process these records in batches of 100 records per batch. How can I make sure that my GroupID's don't get split between different batches? I am fine if each batch is not exactly 100 records, it could be a little more or a little less.
I appreciate any suggestions!
This will result in slightly smaller batches than 100 entries, it'll remove all groups that aren't entirely in the selection;
WITH cte AS (SELECT TOP 100 * FROM (
SELECT GroupID, ROW_NUMBER() OVER (PARTITION BY GroupID ORDER BY GroupID) r
FROM #SomeTestTable) a
ORDER BY GroupID, r DESC)
SELECT c1.GroupID FROM cte c1
JOIN cte c2
ON c1.GroupID = c2.GroupID
AND c2.r = 1
It'll select the groups with the lowest GroupID's, limited to 100 entries into a common table expression along with the row number, then it'll use the row number to throw away any groups that aren't entirely in the selection (row number 1 needs to be in the selection for the group to be, since the row number is ordered descending before cutting with TOP).

Postgres - Get data from each alias

In my application i have a query that do multiple joins with a table position. Just like this:
SELECT *
FROM (...) as trips
join trip as t on trips.trip_id = t.trip_id
left outer join vehicle as v on v.vehicle_id = t.trip_vehicle_id
left outer join position as start on trips.start_position_id = start.position_id and start.position_vehicle_id = v.vehicle_id
left outer join position as "end" on trips.end_position_id = "end".position_id and "end".position_vehicle_id = v.vehicle_id
left outer join position as last on trips.last_position_id = last.position_id and last.position_vehicle_id = v.vehicle_id;
My table position has 35 columns(for example position_id).
When I run the query, in result should appear the table position 3 times, start, end and last. But postgres can not distinguish between, for exemplar, start.position_id, end.position_id and last.position_id. So this 3 columns are group and appear as one, position_id.
As the data from start.position_id and end.position_id are different, the column, position_id, that appear in result, it's empty.
Without having to rename all the columns, like this: start.position_id as start_position_id.
How can i get each group of data separately, for exemple, get all columns from the table 'start'. In MYSQL i can do this operation by calling fetch_fields, and give the function an alias, like 'start'.
But i can i do this in Postgres?
Best Regards,
Nuno Oliveira
My understanding is that you can't (or find it difficult to) discern between which table each column with a shared name (such as "position_id") belongs to, but only need to see one of the sets of shared columns at any one time. If that is the case, use tablename.* in your SELECT, so SELECT trips.*, start.*... would show the columns from trips and start, but no columns from other tables involved in the join.
SELECT [...,] start.* [,...] FROM [...] atable AS start [...]