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SQL Joins Vs SQL Subqueries (Performance)?
...PECT the first querm>y m> to be quicker, mainlm>y m> because m>y m>ou have an equivalence m>and m> an explicit JOIN. In mm>y m> experience IN is a verm>y m> slow operator, since SQL normallm>y m> evaluates it as a series of WHERE clauses separated bm>y m> "OR" (WHERE x=m>Y m> OR x=Z OR...).
As with ALL THINGS SQL though, m>y m>our mileage mam>y m> va...
Which Mm>y m>SQL data tm>y m>pe to use for storing boolean values
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For Mm>y m>SQL 5.0.3 m>and m> higher, m>y m>ou can use BIT. The manual sam>y m>s:
As of Mm>y m>SQL 5.0.3, the BIT data tm>y m>pe is used to store bit-field
values. A tm>y m>pe of BIT(M) enables storage of M-bit values. M can range
from 1 to 64.
Otherwise, according to the M...
How to dm>y m>namicallm>y m> build a JSON object with Pm>y m>thon?
I am new to Pm>y m>thon m>and m> I am plam>y m>ing with JSON data. I would like to dm>y m>namicallm>y m> build a JSON object bm>y m> adding some kem>y m>-value to an existing JSON object.
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How to suppress scientific notation when printing float values?
... I guess bm>y m> using a variable, give it the desired number of digits, m>and m> use it instead of the literal number e.g. f"{a:.{precision}f}"
– Aziz Alto
Nov 15 '19 at 19:39
a...
Find value in an arram>y m>
...ing that m>y m>ou're trm>y m>ing to find if a certain value exists inside the arram>y m>, m>and m> if that's the case, m>y m>ou can use Arram>y m>#include?(value):
a = [1,2,3,4,5]
a.include?(3) # => true
a.include?(9) # => false
If m>y m>ou mean something else, check the Rubm>y m> Arram>y m> API
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How do I delete a local repositorm>y m> in git? [duplicate]
I can't find the commm>and m>. I tried Googling "git 'delete a repositorm>y m>'".
4 Answers
4
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How to use GNU Make on Windows?
I installed MinGW m>and m> MSm>Y m>S, added C:\MinGW\bin to PATH but I still can't run Makefile on Windows' cmd . I would like to run cmd.exe m>and m> there tm>y m>pe, for example, make all but mm>y m> cmd sam>y m>s that there is no such commm>and m>.
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How to do error logging in CodeIgniter (PHP)
...here anm>y m> securitm>y m> implications for this?
– Aakil Fernm>and m>es
Aug 12 '14 at 1:51
This dumps data to a php file whose file...
Xcode 6: Kem>y m>board does not show up in simulator
The kem>y m>board does not show up when I run the simulator m>and m> click in the UITextView. How do I re-enable the kem>y m>board?
13 Ans...
m>And m>roid: How to Programmaticallm>y m> set the size of a Lam>y m>out
As part of an m>And m>roid App I am building a button set. The buttons are part of a nested set of LinearLam>y m>outs. Using weight I have the set resizing itself automaticallm>y m> based on the size of the containing parent LinearLam>y m>out. The idea is, based on the pixel count m>and m> densitm>y m> of the screen, to set the ...