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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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How to create and handle composite primary key in JPA
I want to have versions from the same data entry. In other words, I want to duplicate the entry with another version number.
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How to get cumulative sum
the above select returns me the following.
16 Answers
16
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unique object identifier in javascript
I need to do some experiment and I need to know some kind of unique identifier for objects in javascript, so I can see if they are the same. I don't want to use equality operators, I need something like the id() function in python.
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jQuery - Add ID instead of Class
I'm using the current jQuery :
5 Answers
5
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What are valid values for the id attribute in HTML?
When creating the id attributes for HTML elements, what rules are there for the value?
23 Answers
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Django in / not in query
I'm trying to figure out how to write a 'not in' style query in django.
For example, the query structure I'm thinking of would look like this.
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sqlalchemy flush() and get inserted id?
I want to do something like this:
6 Answers
6
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Foreign Key to multiple tables
I've got 3 relevant tables in my database.
5 Answers
5
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Sample settings.xml for maven
How to configure settings.xml in Maven? Also, please share a sample settings.xml .
3 Answers
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