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Why does this async action hang?
...DBConnection.ExecuteAsync<ResultClass>(
ds => ds.Execute("select slow running data into result"));
}
What's the difference? There's now no awaiting anywhere, so nothing being implicitly scheduled to the UI thread. For simple methods like these that have a single return, there's no...
Securely storing environment variables in GAE with app.yaml
...set them. Here is how:
Go to https://console.cloud.google.com/datastore/
Select your project at the top of the page if it's not already selected.
In the Kind dropdown box, select Settings.
If you ran the code above, your keys will show up. They will all have the value NOT SET. Click each one and s...
Quicksort vs heapsort
...
For any deterministic, constant time pivot selection strategy, you can find an array that produces the O(n^2) worst case. It's not enough to eliminate just the minimum. You have to reliably chose pivots that are within a certain pecrentile band.
–...
Can PostgreSQL index array columns?
... for this test...
SET enable_seqscan TO off;
EXPLAIN ANALYZE
SELECT * FROM "Test" WHERE "Column1" @> ARRAY[20];
Result:
Bitmap Heap Scan on "Test" (cost=4.26..8.27 rows=1 width=32) (actual time=0.014..0.015 rows=2 loops=1)
Recheck Cond: ("Column1" @> '{20}'::integer[])
-&...
Xcode 6 how to enable storyboard zoom?
... any level.. but then it'll snap to, say 100% or 50%. And STILL you can't select items on the Storyboard unless you're at 100%. I'm sorry.. what year is this again ?
– Mike Gledhill
Nov 26 '14 at 7:45
...
RESTful API methods; HEAD & OPTIONS
...e defined by future extensions to HTTP. Content negotiation MAY be used to select the appropriate response format. If no response body is included, the response MUST include a Content-Length field with a field-value of "0".
The Max-Forwards request-header field MAY be used to target a specific proxy...
How to clear a notification in Android
...
I don't know why this isn't upvoted more and selected as the answer. This was the solution I was looking for. Thanks!
– loeschg
Jan 29 '13 at 23:48
3
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How do I build a graphical user interface in C++? [closed]
...ack to the operating system (usually with some kind of special "sleep" or "select" or "yield" function call)
then the yield function will return when the operating system is done, and you have another go around the loop.
There are plenty of resources about event based programming. If you have any ...
Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
Why would you use Expression rather than Func?
...y. Ie. you need database.data.Where(i => i.Id > 0) to be executed as SELECT FROM [data] WHERE [id] > 0. If you just pass in a Func, you've put blinders on your driver and all it can do is SELECT * and then once it's loaded all of that data into memory, iterate through each and filter out ev...