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count(*) vs count(column-name) - which is more correct? [duplicate]
... rows
COUNT(column) counts non-NULLs only
COUNT(1) is the same as COUNT(*) because 1 is a non-null expressions
Your use of COUNT(*) or COUNT(column) should be based on the desired output only.
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When to use std::forward to forward arguments?
...s && ...args)
{
g(std::forward<Args>(args)...);
}
That's because of the reference collapsing rules: If T = U&, then T&& = U&, but if T = U&&, then T&& = U&&, so you always end up with the correct type inside the function body. Finally, you ne...
Set value to NULL in MySQL
I want a value to be set to NULL if nothing is put into the text box in the form I'm submitting. How can I make this happen?
I've tried inserting 'NULL' but this just adds the word NULL into the field.
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Convert normal date to unix timestamp
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edited Feb 12 '18 at 3:38
Pang
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How can I make a button redirect my page to another page? [duplicate]
I have been trying the following:
5 Answers
5
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PCH File in Xcode 6
...ile-New...and don't forget to add it to your LLVM6.0 - Language section of Build Settings as Project/whateveryounamedyourpchfile.pch
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Splitting a Java String by the pipe symbol using split(“|”)
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Wilfred Hughes
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answered May 29 '12 at 9:10
Jigar JoshiJigar Joshi
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Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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Is jQuery “each()” function synchronous?
...only exceptions are AJAX, timers (setTimeout and setInterval), and HTML5 Web Workers.
Your problem is probably somewhere else in your code.
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Python string.replace regular expression [duplicate]
...r.replace() v2|v3 does not recognize regular expressions.
To perform a substitution using a regular expression, use re.sub() v2|v3.
For example:
import re
line = re.sub(
r"(?i)^.*interfaceOpDataFile.*$",
"interfaceOpDataFile %s" % fileIn,
line
)
In a ...