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Why prefer two's complement over sign-and-magnitude for signed numbers?
I'm just curious if there's a reason why in order to represent -1 in binary, two's complement is used: flipping the bits and adding 1?
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INNER JOIN ON vs WHERE clause
...o has a STRAIGHT_JOIN clause.
Using this clause, you can control the JOIN order: which table is scanned in the outer loop and which one is in the inner loop.
You cannot control this in MySQL using WHERE syntax.
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How can I detect if this dictionary key exists in C#?
...n your base namespace to do a check and then call the base's Add method in order to actually add it. Hope this works for you
using System;
using System.Collections.Generic;
using System.Collections;
namespace Main
{
internal partial class Dictionary<TKey, TValue> : System.Collections.Gen...
How to change MySQL data directory?
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Stop MySQL using the following command:
sudo /etc/init.d/mysql stop
Copy the existing data directory (default located in /var/lib/mysql) using the following command:
sudo cp -R -p /var/lib/mysql /newpath
edit the MySQL configuration file with the following command:
s...
How to know when UITableView did scroll to bottom in iPhone
I would like to know when a UITableView did scroll to bottom in order to load and show more content, something like a delegate or something else to let the controller know when the table did scroll to bottom.
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Converting pfx to pem using openssl
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In that case you could reorder the cat command to put it first. like: cat file.key file.nokey.pem > file.combo.pem Unless the file.key itself has multiple in wrong order. But either case, you could likely re-arrange stuff programmatically.
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Why does changing the sum order returns a different result?
Why does changing the sum order returns a different result?
6 Answers
6
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How to find largest objects in a SQL Server database?
... i.index_id <= 1
GROUP BY
t.name, i.object_id, i.index_id, i.name
ORDER BY
object_name(i.object_id)
Of course, you can use another ordering criteria, e.g.
ORDER BY SUM(p.rows) DESC
to get the tables with the most rows, or
ORDER BY SUM(a.total_pages) DESC
to get the tables wit...
What is the meaning of prepended double colon “::”?
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Noteworthy differences:
1) shells tend to use the first match using the ordering in PATH, whereas C++ gives a compiler error when you've been ambiguous.
2) In C++, names without any leading scope can be matched in the current namespace, while most UNIX shells only do that if you put . in the PAT...
What is the common header format of Python files?
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