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Select a Dictionary with LINQ
I have used the "select" keyword and extension method to return an IEnumerable<T> with LINQ, but I have a need to return a generic Dictionary<T1, T2> and can't figure it out. The example I learned this from used something in a form similar to the following:
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Drop data frame columns by name
...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it.
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Visual Studio hot keys change occasionally, specifically F6 vs Ctrl-Shift-B for building. WHY?
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This is because you might have selected "General Development Settings" as your default environment settings for your Visual Studio (which usually we do on the first launch of VS after installing it as it pops up a dialogue box to choose default environment...
Entity Framework and SQL Server View
...mn as a primary key, use NULLIF.
An easy way to apply this is to wrap the select statement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
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How to remove application from app listings on Android Developer Console
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Select Store Presense then Pricing Distribution and select Unpublish from App Availability.
Google's help for this is here: https://support.google.com/googleplay/android-developer/answer/113476#unpublish (as of Feb-2020)
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Heroku Postgres - terminate hung query (idle in transaction)
...'s not desirable or not an option ...)
Find the PID by running this sql:
SELECT pid , query, * from pg_stat_activity
WHERE state != 'idle' ORDER BY xact_start;
(The query may need mending dependent of the version of postgres - eventually, just select * from pg_stat_activity). You'll find the ...
How to alter SQL in “Edit Top 200 Rows” in SSMS 2008
...008 Management Studio, when I right click on a database table and choose " Select Top 100 Rows ", I can then e.g. easily add a "ORDER BY " statement to the SQL. That works fine .
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Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
How to trim a string in SQL Server before 2017?
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SELECT LTRIM(RTRIM(Names)) AS Names FROM Customer
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Jquery select all elements that have $jquery.data()
Select elements that i have previously set with jquery.data();
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