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count(*) vs count(column-name) - which is more correct? [duplicate]
... null.
Therefore COUNT(*) is what you should use. If you're using MyISAM and there is no WHERE clause, then the optimiser doesn't even have to look at the table, since the number of rows is already cached.
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POST data to a URL in PHP
...url_exec( $ch );
This will send the post variables to the specified url, and what the page returns will be in $response.
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How to check if anonymous object has a method?
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Doesn't handle the case where the property is defined, but is not a function.
– matt2000
Aug 29 '18 at 23:42
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How can I pretty-print JSON using node.js?
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in most unix systems (including Mac & Linux..and if I recall BSD), tmp folder exists by default
– Antony
Jan 16 '13 at 20:28
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Linq select objects in list where exists IN (A,B,C)
...ad of array for allowedStatus because HashSet's contains method is fastest and there'll be performance issues with array if it contains more than 1000 items. var allowedStatus = new HashSet<string> { "A", "B", "C" };
– Jay Shah
Nov 9 '18 at 18:14
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How to randomly select an item from a list?
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Use random.choice()
import random
foo = ['a', 'b', 'c', 'd', 'e']
print(random.choice(foo))
For cryptographically secure random choices (e.g. for generating a passphrase from a wordlist) use secrets.choice()
import secrets
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“FOUNDATION_EXPORT” vs “extern”
...ill see that FOUNDATION_EXPORT compiles to extern in C, extern "C" in C++, and other things in Win32. So, it's more compatible across languages and operating systems. For many projects, this won't make any difference.
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Set value to NULL in MySQL
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You're probably quoting 'NULL'. NULL is a reserved word in MySQL, and can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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Correct way to use get_or_create?
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@zypro It's like create(), create object and save it all in one step and doesn't need any save()
– Amin Mir
Jun 19 at 6:05
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z-index not working with position absolute
I opened the console (chrome\firefox) and ran the following lines:
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