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How to implement a good __hash__ function in python [duplicate]
... are equal. It also shouldn't change over the lifetime of the object; generally you only implement it for immutable objects.
A trivial implementation would be to just return 0. This is always correct, but performs badly.
Your solution, returning the hash of a tuple of properties, is good. But note...
How to implement a many-to-many relationship in PostgreSQL?
... -- explicit pk
);
I made a few adjustments:
The n:m relationship is normally implemented by a separate table - bill_product in this case.
I added serial columns as surrogate primary keys. In Postgres 10 or later consider an IDENTITY column instead. See:
Safely rename tables using serial primary...
How to create a custom attribute in C#
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will i really like the answer and specially ",one more question i can put same condition in set statement of the above code so how it different from attributs,
– slash shogdhe
Feb 2 '11 at 20:58
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What exactly is Python's file.flush() doing?
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There's typically two levels of buffering involved:
Internal buffers
Operating system buffers
The internal buffers are buffers created by the runtime/library/language that you're programming against and is meant to speed things up by ...
.NET Global exception handler in console application
...ots of technologies to run in different threads. For example, the Task Parallel Library (TPL) has its own way to catch unhandled exceptions. So, saying this doesn't work for all situations is kind of ludicrous, there is NO one place catch-all for everything in C#, but depending on the technologies...
How to track down log4net problems
I use log4net all the time, but one thing I've never figured out is how to tell what's going on on the inside. For example, I've got a console appender and a database appender in my project. I made a few changes to the database and the code, and now the database appender doesn't work anymore. I'll f...
Viewing unpushed Git commits
... I've made, that haven't yet been pushed to the remote repository? Occasionally, git status will print out that my branch is X commits ahead of origin/master , but not always.
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How do I import other TypeScript files?
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You can use the --all flag with tsc on your main .ts file. The compiler figures out all the dependencies based on your reference tags and generates a single output .js file for the entire application: tsc --out app.js main.ts
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Transactions in .net
...in C# .Net 2.0. What are the classes that should be used? What are the pitfalls to look out for etc. All that commit and rollback stuff. I'm just starting a project where I might need to do some transactions while inserting data into the DB. Any responses or links for even basic stuff about transact...
How do I use VaryByParam with multiple parameters?
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You can use * for all parameters or a semi-colon separated list (VaryByParam = "customerId;languageId").
You can also use none if you didn't want it to cache different versions....
Here's a nice write up specifically for MVC.
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