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SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...
How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
Checking if a string can be converted to float in Python
...False
print(isfloat("12.34.56")) False Two dots not allowed.
print(isfloat("#56")) False
print(isfloat("56%")) False
print(isfloat("0E0")) True
print(isfloat("x86E0")) False
print(isfloat("86-5")) ...
What is the best practice for “Copy Local” and with project references?
...===================
GetCopyToOutputDirectoryItems
Get all project items that may need to be transferred to the
output directory.
============================================================ -->
<Target
Name="GetCopyToOutputDirectoryItems"
Outputs="@(AllItemsFullPat...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...
int may be as small as 16 bits on some platforms. It may not be sufficient for your application.
uint32_t is not guaranteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactl...
How do I get the path of the current executed file in Python?
...ike a newbie question, but it is not. Some common approaches don't work in all cases:
13 Answers
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How to divide flask app into multiple py files?
...c resources: templates or static files. Please refer to the Flask docs for all the details.
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Truncating all tables in a Postgres database
I regularly need to delete all the data from my PostgreSQL database before a rebuild. How would I do this directly in SQL?
...
__proto__ VS. prototype in JavaScript
...x = x;
this.y = y;
}
var myPoint = new Point();
// the following are all true
myPoint.__proto__ == Point.prototype
myPoint.__proto__.__proto__ == Object.prototype
myPoint instanceof Point;
myPoint instanceof Object;
Here Point is a constructor function, it builds an object (data structure) p...
What is the best way to call a script from another script?
...s, methods, etc. I have another script which runs as a service. I want to call test1.py from the script running as a service.
...