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Shell - How to find directory of some command?
...d that this was just an alias defined on my .bashrc located on my ~home. Really thank you.
– Gabriel L. Oliveira
May 20 '10 at 13:36
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GitHub README.md center image
...(as rightfully pointed out by @waldyr.ar), and in the GitHub case you may fallback to something like <div style="text-align:center"><img src="..." /></div>. Beware that there's no guarantee the image will be centered if your repository is forked in a different hosting environment (...
How do I modify fields inside the new PostgreSQL JSON datatype?
...a":[null,{"b":[1,2,3]}]}'
For inserting into JSON array (while preserving all of the original values), the jsonb_insert() function can be used (in 9.6+; this function only, in this section):
SELECT jsonb_insert('{"a":[null,{"b":[1]}]}', '{a,1,b,0}', jsonb '2')
-- will yield jsonb '{"a":[null,{"b":[...
How to get cumulative sum
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@Franklin Only cost efficient for small tables. Cost grows proportional to the square of the number of rows. SQL Server 2012 allows this to be done much more efficiently.
– Martin Smith
May 18 '13 at 19:57
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Cryptic “Script Error.” reported in Javascript in Chrome and Firefox
...xternal domains. For an example of why this is necessary, imagine accidentally visiting evilsite.com, that serves up a page with <script src="yourbank.com/index.html">. (yes, we're pointing that script tag at html, not JS). This will result in a script error, but the error is interesting be...
Bitwise operation and usage
...Bitwise operators are operators that work on multi-bit values, but conceptually one bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1...
Why is the use of tuples in C++ not more common?
... but I often see lots of places where tuples would solve many problems (usually returning multiple values from functions).
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How to speed up insertion performance in PostgreSQL
...u've batched your work into big transactions, though.
INSERT or COPY in parallel from several connections. How many depends on your hardware's disk subsystem; as a rule of thumb, you want one connection per physical hard drive if using direct attached storage.
Set a high checkpoint_segments value an...
Objective-C for Windows
...X so that any viable OS X program can run on Windows. Because GNUStep typically uses the latest version of gcc, they also add in support for Objective-C++ and a lot of the Objective-C 2.0 features.
I haven't tested those features with GNUStep, but if you use a sufficiently new version of gcc, you m...
What does android:layout_weight mean?
... You do need the 0px. Example: you want to implement a table with two equally-sized columns. Each table row is a horizontal linear layout with two "table cells" (for example, TextViews), each one having layout_weight=.5. If you specify layout_width="wrap_content" on the "table cells," the conten...