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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...ND_ROWS?
Just a quick summary: Peter says that it depends on your indexes and other factors. Many of the comments to the post seem to say that SQL_CALC_FOUND_ROWS is almost always slower - sometimes up to 10x slower - than running two queries.
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Rearrange columns using cut
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For the cut(1) man page:
Use one, and only one of -b, -c or -f. Each LIST is made up of
one
range, or many ranges separated by commas. Selected input is written
in the same order that it is read, and is written exactly once.
It ...
Docker - how can I copy a file from an image to a host?
...ckerfile that fetches dependencies, compiles a build artifact from source, and runs an executable. I also want to copy the build artifact (in my case it's a .zip produced by sbt dist in '../target/`, but I think this question also applies to jars, binaries, etc.
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How to calculate an angle from three points? [closed]
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Only a handful of languages use a caret for 'power of', so if you don't want to call it arcos, please just type cos⁻¹. (If you're using a commercial operating system that makes it difficult to type exponents, I expect there would ...
Hidden features of mod_rewrite
...of it work. As a result I've compiled a few notes on common functionality, and perhaps a few annoying nuances.
8 Answers
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iReport not starting using JRE 8
I have downloaded and installed the iReport 4.5 using te Windows installer. But when I try to start the iReport it shows the splash screen but does not start.
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curl: (60) SSL certificate problem: unable to get local issuer certificate
...mportant to note that this applies to the system sending the CURL request, and NOT the server receiving the request.
Download the latest cacert.pem from https://curl.haxx.se/ca/cacert.pem
Add the following line to php.ini: (if this is shared hosting and you don't have access to php.ini then you c...
What's the best way to build a string of delimited items in Java?
...,char)
Java 8:
Java 8 provides joining out of the box via StringJoiner and String.join(). The snippets below show how you can use them:
StringJoiner
StringJoiner joiner = new StringJoiner(",");
joiner.add("01").add("02").add("03");
String joinedString = joiner.toString(); // "01,02,03"
Str...
Why and not taking font-family and font-size from body?
Why Textarea and textfield not taking font-family and font-size from body?
5 Answers
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Purge or recreate a Ruby on Rails database
...ave a dev Ruby on Rails database full of data. I want to delete everything and rebuild the database. I'm thinking of using something like:
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