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mongo group query how to keep fields
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@Juliomac, I believe if your desired output is $max/$min and keeping fields that are not in the $group _id, you can $sort before with the desired field then group and use $first or $last operators on any field. When accumulating, the idea to include other fields (which are accumula...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
...ows however. SELECT DISTINCT won't work because it operates on all columns and I need to suppress duplicates based on the key columns.
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CSS – why doesn’t percentage height work? [duplicate]
...</div>
#inner will grow to be tall enough to contain the paragraph and #outer will grow to be tall enough to contain #inner.
When you specify the height or width as a percentage, that's a percentage with respect to the element's parent. In the case of width, all block elements are, unless s...
How do I set the offset for ScrollSpy in Bootstrap?
I have a site with the navbar fixed on top and 3 divs underneath in the main content area.
12 Answers
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How to make custom error pages work in ASP.NET MVC 4
I want a custom error page shown for 500, 404 and 403. Here's what I have done:
11 Answers
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CSS selector with period in ID
...ng through all the specs writing the question, I read through it some more and found there is an escape character. I've never needed it before, but the CSS spec does allow for backslash (\) escaping like most languages. What do you know?
So in my example, the following rule would match:
#some\.id ...
Change the name of the :id parameter in Routing resources for Rails
I looked around on how to change the dynamic params slot and found this post that does the exact thing.
The post is https://thoughtbot.com/blog/rails-patch-change-the-name-of-the-id-parameter-in
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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...y.
Side effects are propagated to replicas too.
correction: both REPLACE and INSERT...ON DUPLICATE KEY UPDATE are non-standard, proprietary inventions specific to MySQL. ANSI SQL 2003 defines a MERGE statement that can solve the same need (and more), but MySQL does not support the MERGE statemen...
What's the difference between session.persist() and session.save() in Hibernate?
...red.
save() does not guarantee the same, it
returns an identifier, and if an
INSERT has to be executed to get the
identifier (e.g. "identity" generator,
not "sequence"), this INSERT happens
immediately, no matter if you are
inside or outside of a transaction.
This is not good in ...
Count with IF condition in MySQL query
I have two tables, one is for news and the other one is for comments and I want to get the count of the comments whose status has been set as approved.
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