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quick random row selection in Postgres
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Check this link out for some different options.
http://www.depesz.com/index.php/2007/09/16/my-thoughts-on-getting-random-row/
Update: (A.Hatchkins)
The summary of the (very) long article is as follows.
The author lists four approaches:
1) ORDER BY random() LIMIT 1; -- slow
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Difference between map and collect in Ruby?
...Actually they are documented in the same place under ruby-doc.org:
http://www.ruby-doc.org/core/classes/Array.html#M000249
ary.collect {|item| block } → new_ary
ary.map {|item| block } → new_ary
ary.collect → an_enumerator
ary.map → an_enumerator
Invokes block once for ...
How do I move a file with Ruby?
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Use the module 'fileutils' and use FileUtils.mv:
http://www.ruby-doc.org/stdlib-2.0/libdoc/fileutils/rdoc/FileUtils.html#method-c-mv
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Dictionaries and default values
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For multiple different defaults try this:
connectionDetails = { "host": "www.example.com" }
defaults = { "host": "127.0.0.1", "port": 8080 }
completeDetails = {}
completeDetails.update(defaults)
completeDetails.update(connectionDetails)
completeDetails["host"] # ==> "www.example.com"
complete...
jQuery/JavaScript to replace broken images
...tibility table lists the browsers that support the error facility:
http://www.quirksmode.org/dom/events/error.html
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CSS: Change image src on img:hover
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.img-wrapper {
display: inline-block;
background-image: url(https://www.w3schools.com/w3images/fjords.jpg);
}
.img-wrapper > img {
vertical-align: top;
}
.img-wrapper > img:hover {
opacity: 0;
}
<div class="img-wrapper">
<img src="https://www.w3schools.com/w3...
Verify a certificate chain using openssl verify
...ck' 0
serve()
{
kick
PID=
openssl s_server -key "$KEY" -cert "$CRT" "$@" -www &
PID=$!
sleep .5 # give it time to startup
}
check()
{
while read -r line
do
case "$line" in
'Verify return code: 0 (ok)') return 0;;
'Verify return code: '*) return 1;;
# *) echo "::: $line :...
Add Text on Image using PIL
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First, you have to download a font type...for example: https://www.wfonts.com/font/microsoft-sans-serif.
After that, use this code to draw the text:
from PIL import Image
from PIL import ImageFont
from PIL import ImageDraw
img = Image.open("filename.jpg")
draw = ImageDraw.Draw(img)
fo...
Jump to function definition in vim
...ol under cursor.
Here is the most downloaded plugin for navigation
http://www.vim.org/scripts/script.php?script_id=273
Here is one I've written to select context while jump to tag
http://www.vim.org/scripts/script.php?script_id=2507
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How to pretty print XML from Java?
...?><QueryMessage\n" +
" xmlns=\"http://www.SDMX.org/resources/SDMXML/schemas/v2_0/message\"\n" +
" xmlns:query=\"http://www.SDMX.org/resources/SDMXML/schemas/v2_0/query\">\n" +
" <Query>\n" +
...