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Row count with PDO
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$sql = "SELECT count(*) FROM `table` WHERE foo = ?";
$result = $con->prepare($sql);
$result->execute([$bar]);
$number_of_rows = $result->fetchColumn();
Not the most elegant way to do it, plus it involves an extra query...
How do I find numeric columns in Pandas?
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You could use select_dtypes method of DataFrame. It includes two parameters include and exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numer...
Visual Studio : short cut Key : Duplicate Line
...ure is now built-in in VS2017: Ctrl + E, V duplicates a line if nothing is selected, or duplicates selection. You can assign it to a different key combination, or find it in the menu:
See this reference for more information.
Pre VS2017, built-in method using clipboard
As @cand mentioned, you ca...
Generating random numbers in Objective-C
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arc4random_stir(void);
void
arc4random_addrandom(unsigned char *dat, int datlen);
DESCRIPTION
The arc4random() function uses the key stream generator employed by the arc4 cipher, which uses 8*8 8
bit S-Boxes. The S-Boxes can be in about (2**1700) states. The arc4random(...
What is the purpose of Order By 1 in SQL select statement?
...number stands for the column based on the number of columns defined in the SELECT clause. In the query you provided, it means:
ORDER BY A.PAYMENT_DATE
It's not a recommended practice, because:
It's not obvious/explicit
If the column order changes, the query is still valid so you risk ordering ...
ng-options with simple array init
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You actually had it correct in your third attempt.
<select ng-model="myselect" ng-options="o as o for o in options"></select>
See a working example here:
http://plnkr.co/edit/xEERH2zDQ5mPXt9qCl6k?p=preview
The trick is that AngularJS writes the keys as numbers from...
Understanding colors on Android (six characters)
...ed as RGB or ARGB.
http://en.wikipedia.org/wiki/ARGB
In RGB you have two characters for every color (red, green, blue), and in ARGB you have two additional chars for the alpha channel.
So, if you have 8 characters, it's ARGB, with the first two characters specifying the alpha channel. If you remo...
Rails: select unique values from a column
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Model.select(:rating)
Result of this is a collection of Model objects. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (mo...
Pad a number with leading zeros in JavaScript [duplicate]
...hem as if their value is the empty string. Thus you get a copy of the zero character (or whatever "z" is) between each of the array elements; that's why there's a + 1 in there.
Example usage:
pad(10, 4); // 0010
pad(9, 4); // 0009
pad(123, 4); // 0123
pad(10, 4, '-'); // --10
...
How to read a file into a variable in shell?
...ther answers so far:
Trailing newline removal from command expansion
NUL character removal
Trailing newline removal from command expansion
This is a problem for the:
value="$(cat config.txt)"
type solutions, but not for read based solutions.
Command expansion removes trailing newlines:
S="...