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What can , and be used for?
Can anyone clarify how we can use in general, or a in real world example, this snippet?
2 Answers
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Rails :include vs. :joins
This is more of a "why do things work this way" question rather than a "I don't know how to do this" question...
8 Answers
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Can I specify multiple users for myself in .gitconfig?
In my ~/.gitconfig , I list my personal email address under [user] , since that's what I want to use for Github repos.
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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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jquery IDs with spaces
Does anyone know how to select an item in the DOM by ID with jQuery, when that ID has a space?
11 Answers
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NullPointerException accessing views in onCreate()
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The tutorial is probably outdated, attempting to create an activity-based UI instead of the fragment-based UI preferred by wizard-generated code.
The view is in the fragment layout (fragment_main.xml) and not in the activity layout (activity_main.xml). onCreate() i...
Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
Why am I getting this exception?
9 Answers
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Remove Identity from a column in a table
...remove the entire column:
ALTER TABLE yourTable
DROP COLUMN yourCOlumn;
Information about ALTER TABLE here
If you need to keep the data, but remove the IDENTITY column, you will need to:
Create a new column
Transfer the data from the existing IDENTITY column to the new column
Drop the existing...
SQL select only rows with max value on a column [duplicate]
...ticed you need the content column as well.
This is a very common question in SQL: find the whole data for the row with some max value in a column per some group identifier. I heard that a lot during my career. Actually, it was one the questions I answered in my current job's technical interview.
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Hibernate, @SequenceGenerator and allocationSize
We all know the default behaviour of Hibernate when using @SequenceGenerator - it increases real database sequence by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
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