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What regular expression will match valid international phone numbers?
I need to determine whether a phone number is valid before attempting to dial it. The phone call can go anywhere in the world.
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When to use “ON UPDATE CASCADE”
...pplicable if we're assuming that the parent key is not updateable? Here is one case.
I am dealing with a replication scenario in which multiple satellite databases need to be merged with a master. Each satellite is generating data on the same tables, so merging of the tables to the master leads to ...
How do I find duplicate values in a table in Oracle?
...by COUNT, then use a HAVING clause to find values that appear greater than one time.
SELECT column_name, COUNT(column_name)
FROM table_name
GROUP BY column_name
HAVING COUNT(column_name) > 1;
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How well is Unicode supported in C++11?
...put/output library
Regular expressions library
I think all but the first one provide terrible support. I'll get back to it in more detail after a quick detour through your other questions.
Does std::string do what it should?
Yes. According to the C++ standard, this is what std::string and it...
Peak-finding algorithm for Python/SciPy
...ms like a common-enough function to be included in standard libraries. Anyone know of one?
8 Answers
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How do I keep CSS floats in one line?
I want to have two items on the same line using float: left for the item on the left.
10 Answers
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pyplot scatter plot marker size
...h circle (as we move from left to right) it's width is double the previous one so for the area this is an exponential with base 4. Similarly the second example each circle has area double the last one which gives an exponential with base 2.
However it is the second example (where we are scaling are...
Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
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One reason that selecting specific columns is better is that it raises the probability that SQL Server can access the data from indexes rather than querying the table data.
Here's a post I wrote about it: The real reason s...
Postgresql GROUP_CONCAT equivalent?
I have a table and I'd like to pull one row per id with field values concatenated.
7 Answers
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Python division
... becoming a floating point number.
>>> 1 / 2
0
You should make one of them a float:
>>> float(10 - 20) / (100 - 10)
-0.1111111111111111
or from __future__ import division, which the forces / to adopt Python 3.x's behavior that always returns a float.
>>> from __futu...