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What's the best practice for primary keys in tables?
...ary. Prefer a numeric type because numeric types are stored in a much more compact format than character formats. This is because most primary keys will be foreign keys in another table as well as used in multiple indexes. The smaller your key, the smaller the index, the less pages in the cache you ...
How to find the statistical mode?
...
Gregor Thomas
91.9k1515 gold badges126126 silver badges235235 bronze badges
answered Sep 3 '14 at 3:21
jprockbellyj...
Visualizing branch topology in Git
... and I find it difficult to maintain a mental model of all my branches and commits. I know I can do a git log to see the commit history from where I am, but is there a way to see the entire branch topography, something like these ASCII maps that seem to be used everywhere for explaining branches?
...
How do I make Git ignore file mode (chmod) changes?
...
3919
Try:
git config core.fileMode false
From git-config(1):
core.fileMode
Tells Git if th...
How to access the last value in a vector?
... min lq mean median uq max neval
x[length(x)] 171 291.5 388.91 337.5 390.0 3233 100
mylast(x) 1291 1832.0 2329.11 2063.0 2276.0 19053 100
tail(x, n = 1) 7718 9589.5 11236.27 10683.0 12149.0 32711 100
dplyr::last(x) 16341 19049.5 22080.23 21673.0 23...
How does this CSS produce a circle?
...
How does a border of 180 pixels with height/width-> 0px become a circle with a radius of 180 pixels?
Let's reformulate that into two questions:
Where do width and height actually apply?
Let's have a look at the areas of a typical box (source):
The height and width apply only ...
Xcode duplicate/delete line
...
91
The whole point is NOT to use the Cmd-C/Cmd-V shortcuts. I have the same issue coming from Inte...
techniques for obscuring sensitive strings in C++
...OR key2
If you create key1 with the same byte-length as key you can use (completely) random byte values and then compute key2:
key1[n] = crypto_grade_random_number(0..255)
key2[n] = key[n] XOR key1[n]
You can do this in your build environment, and then only store key1and key2 in your applicatio...
What regular expression will match valid international phone numbers?
... that the country code is valid.
^011(999|998|997|996|995|994|993|992|991|
990|979|978|977|976|975|974|973|972|971|970|
969|968|967|966|965|964|963|962|961|960|899|
898|897|896|895|894|893|892|891|890|889|888|
887|886|885|884|883|882|881|880|879|878|877|
876|875|874|873|872|871|870|859...
Is MATLAB OOP slow or am I doing something wrong?
...th=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4...