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How can I select rows with most recent timestamp for each key value?
...r data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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How to load assemblies in PowerShell?
...me;
These should also work:
Add-Type -AssemblyName $TypeName -PassThru | Select-Object -ExpandProperty Assembly | Select-Object -ExpandProperty FullName -Unique
If I want my script to always use a specific version of a .dll but I can't be certain of where it's installed, how do I determine what ...
How to get the selected index of a RadioGroup in Android
Is there an easy way to get the selected index of a RadioGroup in Android or do I have to use OnCheckedChangeListener to listen for changes and have something that holds the last index selected?
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TransformXml task could not be loaded from Microsoft.Web.Publishing.Tasks.dll
...o Installer in your computer
Click or tap to start the installer, and then select Modify.
From the Individual Components screen, select Asp.net and web development tools and then select Modify/Install.
This solved the issue as it creates the dll's in the mentioned path.
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IntelliJ and Tomcat.. Howto..?
..., so Idea will know about your tomcat server
3) Go to Deployment tab and select Artifact. Apply
4) In src folder put your servlet (you can try my example for testing purpose)
5) Go to web.xml file and link your's servlet like this
6) In web folder put your's .jsp files (for example hey.jsp...
What is the difference between Views and Materialized Views in Oracle?
... you. The downside of a view is that its performance depends on how good a select statement the view is based on. If the select statement used by the view joins many tables, or uses joins based on non-indexed columns, the view could perform poorly.
Materialized views
They are similar to regular vi...
What is the reason for a red exclamation mark next to my project in Eclipse?
...rors can be seen in the Problems view, and if you open
the view menu and select Group By > Java Problem Type, they all show
up in the Build Path category:
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Selecting only numeric columns from a data frame
...traightforward, and robust to use on database-back-ended tibbles:
dplyr::select_if(x, is.numeric)
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Only one expression can be specified in the select list when the subquery is not introduced with EXI
...column on the other side of the IN. So the query needs to be of the form:
SELECT * From ThisTable WHERE ThisColumn IN (SELECT ThatColumn FROM ThatTable)
You also want to add sorting so you can select just from the top rows, but you don't need to return the COUNT as a column in order to do your so...
Excel Date to String conversion
...ard. It's found under the Data tab in Excel 2007.
If you have one column selected, the defaults for file type and delimiters should work, then it prompts you to change the data format of the column. Choosing text forces it to text format, to make sure that it's not stored as a date.
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