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Join vs. sub-query

.... It all depends on the data, indexes, correlation, amount of data, query, etc. share | improve this answer | follow | ...
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How to use the CancellationToken property?

... have some logical condition to exit (iterate over all items in collection etc.). So I believe it's better not to mix that conditions as they have different intention. Cautionary note about avoiding CancellationToken.ThrowIfCancellationRequested(): Comment in question by Eamon Nerbonne: ... r...
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Selecting with complex criteria from pandas.DataFrame

...that & operator takes a precedence over operators such as > or < etc. That is why 4 < 5 & 6 > 4 evaluates to False. Therefore if you're using pd.loc, you need to put brackets around your logical statements, otherwise you get an error. That's why do: df.loc[(df['A'] > 10) ...
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What's the best way to share data between activities?

...ashMap of WeakReferences Persist objects (sqlite, share preferences, file, etc.) TL;DR: there are two ways of sharing data: passing data in the intent's extras or saving it somewhere else. If data is primitives, Strings or user-defined objects: send it as part of the intent extras (user-defined ob...
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What does the caret operator (^) in Python do?

...an do binary numbers by typing 0bX where X is your binary. 0b0001, 0b0010, etc. So, 0b1101 ^ 0b1110 would give you 0b0011 (or 3). – Jeff Jul 28 '15 at 23:58 ...
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Why does Math.round(0.49999999999999994) return 1?

...s (CPU, 32- or 64-bit mode). And, when using round or inverting matrices, etc., these bits can make a huge difference. x64 output: 10.5 rounded is 11 10.499999999999998 rounded is 10 9.5 rounded is 10 9.499999999999998 rounded is 9 8.5 rounded is 9 8.499999999999998 rounded is 8 7.5 rounded is 8 ...
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How to display gpg key details without importing it?

... ACK, this is very good, doesn't require local personal keyring etc. does display the key name... works best. – Florian Heigl Apr 30 '17 at 16:22 ...
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What difference is there between WebClient and HTTPWebRequest classes in .NET?

...n fact, why weren't they merged into one class (too many methods/variables etc may be one reason but there are other classes in .NET which breaks that rule). ...
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Handling warning for possible multiple enumeration of IEnumerable

...ave an interface that is IEnumerable + Count + Indexer, without Add/Remove etc. methods, which is what I suspect would solve this problem. share | improve this answer | foll...
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Naming of ID columns in database tables

...ys have table alias such as "i" for inoice, p for "product" on SQL or LINQ etc. – Cheung Oct 13 '14 at 7:50 ...