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How to create an object for a Django model with a many to many field?
...my original suggestion. It works, but isn't optimal. (Note: I'm using Bars and a Foo instead of Users and a Sample, but you get the idea).
bar1 = Bar.objects.get(pk=1)
bar2 = Bar.objects.get(pk=2)
foo = Foo()
foo.save()
foo.bars.add(bar1)
foo.bars.add(bar2)
It generates a whopping total of 7 quer...
How can I get the ID of an element using jQuery?
Why doesn't the above work, and how should I do this?
19 Answers
19
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When use getOne and findOne methods Spring Data JPA
...ing a method on it is required.
findOne()/findById() is really more clear and simple to use than getOne().
So in the very most of cases, favor findOne()/findById() over getOne().
API Change
From at least, the 2.0 version, Spring-Data-Jpa modified findOne().
Previously, it was defined in the Cru...
Schema for a multilanguage database
...es, localizability is not an issue. We can use language specific resources and have all kinds of tools that work well with them.
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ActiveRecord.find(array_of_ids), preserving order
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.ids works fine for me, and is pretty fast activerecord documentation
– TheJKFever
Jul 8 '15 at 15:26
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Many-to-many relationship with the same model in rails?
...documentation on the subject. There's a section called “Many-to-many”, and of course the documentation on the class methods themselves.
Simplest scenario, uni-directional, no additional fields
This is the most compact in code.
I'll start out with this basic schema for your posts:
create_tabl...
What is the id( ) function used for?
I read the Python 2 docs and noticed the id() function:
13 Answers
13
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Retrieving the last record in each group - MySQL
...dowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1...
SQL server query to get the list of columns in a table along with Data types, NOT NULL, and PRIMARY
... of columns in a particular table, its associated data types (with length) and if they are not null. And I have managed to do this much.
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Real life example, when to use OUTER / CROSS APPLY in SQL
I have been looking at CROSS / OUTER APPLY with a colleague and we're struggling to find real life examples of where to use them.
...