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PDO closing connection
Just a rather simple question with regards to PDO compared to MySQLi.
5 Answers
5
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Getting distance between two points based on latitude/longitude
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Edit: Just as a note, if you just need a quick and easy way of finding the distance between two points, I strongly recommend using the approach described in Kurt's answer below instead of re-implementing Haversine -- see his po...
How do I get my Python program to sleep for 50 milliseconds?
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edited Feb 10 '19 at 19:47
ruwan800
54499 silver badges1515 bronze badges
answer...
Rails: around_* callbacks
...cks are invoked before the action, then when you want to invoke the action itself, you yield to it, then continue execution. That's why it's called around
The order goes like this: before, around, after.
So, a typical around_save would look like this:
def around_save
#do something...
yield ...
Assigning a variable NaN in python without numpy
...stant you can use to assign a variable the value NaN. Can python do this without using numpy?
6 Answers
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Flask-SQLalchemy update a row's information
...tutorial shown in the Flask-SQLAlchemy documentation. Once you have the entity that you want to change, change the entity itself. Then, db.session.commit().
For example:
admin = User.query.filter_by(username='admin').first()
admin.email = 'my_new_email@example.com'
db.session.commit()
user = User...
JavaScript: What are .extend and .prototype used for?
...eing .extend and .prototype in third party libraries I am using. I thought it had to do with the Prototype javascript library, but I am beginning to think that is not the case. What are these used for?
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How to get the original value of an attribute in Rails
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Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should ap...
Dashed line border around UIView
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You can set the border with this pattern using Layer and Bezier path like below examples.
Objective-C
CAShapeLayer *yourViewBorder = [CAShapeLayer layer];
yourViewBorder.strokeColor = [UIColor blackColor].CGColor;
yourViewBorder.fillColor = nil;
y...
How to copy a row and insert in same table with a autoincrement field in MySQL?
In MySQL I am trying to copy a row with an autoincrement column ID=1 and insert the data into same table as a new row with column ID=2 .
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