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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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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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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 ...
In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros? [dupli
...oach would be to check how many digits are output by Integer.toHexString() and add a leading zero to each byte if needed. Something like this:
public static String toHexString(byte[] bytes) {
StringBuilder hexString = new StringBuilder();
for (int i = 0; i < bytes.length; i++) {
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How many and which are the uses of “const” in C++?
...y obscure to me, one of these is const . You can use it in so many places and with so many different effects that is nearly impossible for a beginner to come out alive. Will some C++ guru explain once forever the various uses and whether and/or why not to use them?
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Dealing with commas in a CSV file
I am looking for suggestions on how to handle a csv file that is being created, then uploaded by our customers, and that may have a comma in a value, like a company name.
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What is the use of Enumerable.Zip extension method in Linq?
...ative. B) Write a method to yield return each element of the shorter list, and then continue yield returning default indefinitely thereafter. (Option B requires you to know in advance which list is shorter.)
– jpaugh
Jul 7 '17 at 21:41
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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...
Difference between “module.exports” and “exports” in the CommonJs Module System
...ariables to the same object, they are all the same object; so then exports and module.exports are the same object.
But if you set exports to something new, it will no longer be set to module.exports, so exports and module.exports are no longer the same object.
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Shall we always use [unowned self] inside closure in Swift
In WWDC 2014 session 403 Intermediate Swift and transcript , there was the following slide
9 Answers
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