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How to select the row with the maximum value in each group
In a dataset with multiple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
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Similar to jQuery .closest() but traversing descendants?
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These examples all select depth-first descendants, not breadth-first, so these can't be used to solve the original question. In my testing they all returned the first span, not the second.
– JrBaconCheez
M...
C programming in Visual Studio
...project (not for the solution), expand Configuration Properties, C/C++ and select Advanced. Change the Compile As setting to Compile as C Code (/TC).
https://docs.microsoft.com/en-us/cpp/ide/visual-cpp-project-types?view=vs-2017
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Exit single-user mode
...tabase in MULTI_USER mode.
USE master
GO
DECLARE @kill varchar(max) = '';
SELECT @kill = @kill + 'KILL ' + CONVERT(varchar(10), spid) + '; '
FROM master..sysprocesses
WHERE spid > 50 AND dbid = DB_ID('<Your_DB_Name>')
EXEC(@kill);
GO
SET DEADLOCK_PRIORITY HIGH
ALTER DATABASE [<Your_DB...
Selecting with complex criteria from pandas.DataFrame
...se pandas it has some built in functions for comparison. So if you want to select values of "A" that are met by the conditions of "B" and "C" (assuming you want back a DataFrame pandas object)
df[['A']][df.B.gt(50) & df.C.ne(900)]
df[['A']] will give you back column A in DataFrame format.
pan...
How to get the index of an element in an IEnumerable?
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extensions with overloads like Select((x, i) => ...) seem to imply that these indexes should exist
– Michael
Mar 19 '14 at 16:05
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How to do a join in linq to sql with method syntax?
...eOtherClass
on sc.Property1 equals soc.Property2
select new { SomeClass = sc, SomeOtherClass = soc };
Would be equivalent to:
var result = enumerableOfSomeClass
.Join(enumerableOfSomeOtherClass,
sc => sc.Property1,
soc => soc.Property2,
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PostgreSQL: Show tables in PostgreSQL
...a:
\dt
Programmatically (or from the psql interface too, of course):
SELECT * FROM pg_catalog.pg_tables;
The system tables live in the pg_catalog database.
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How to set auto increment primary key in PostgreSQL?
...able(moobars,foobars) values('worldwide interblag','2012-05-02')
Step 3, select * from your table:
el@voyager$ psql -U pgadmin -d kurz_prod -c "select * from epictable"
Step 4, interpret the output:
mytable_key | moobars | foobars
-------------+-----------------------+------...
Can I create a One-Time-Use Function in a Script or Stored Procedure?
... create temp stored procedures like:
create procedure #mytemp as
begin
select getdate() into #mytemptable;
end
in an SQL script, but not functions. You could have the proc store it's result in a temp table though, then use that information later in the script ..
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