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Finding duplicate values in a SQL table
...ly group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attributes in a relation...
What is the dual table in Oracle?
...of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
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NoSQL (MongoDB) vs Lucene (or Solr) as your database
...arned:
You can easily use Lucene/Solr in lieu of MongoDB for pretty much all situations, but not vice versa. Grant Ingersoll's post sums it up here.
MongoDB etc. seem to serve a purpose where there is no requirement of searching and/or faceting. It appears to be a simpler and arguably easier trans...
Is there any git hook for pull?
...ot on there, it doesn't exist.
That said, there is a post-merge hook, and all pulls include a merge, though not all merges are pulls. It's run after merges, and can't affect the outcome. It never gets executed if there were conflicts; you'd have to pick that up with the post-commit hook if it reall...
SQL update query using joins
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I usually start with semicolon to terminate previous statement (if any). CTE rocks ! Simple to design complicated query / joined updates. I use it all the time...
– Adam W
Dec 17 '15 at 5:19
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Get MIME type from filename extension
...dd double checks and provide fail safe action for every step.
MimeMapping._mappingDictionary.AddMapping(string fileExtension, string mimeType)
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What's the difference between Unicode and UTF-8? [duplicate]
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most editors support save as ‘Unicode’ encoding actually.
This is an unfortunate misnaming perpetrated by Windows.
Because Windows uses UTF-16LE encoding internally as the memory storage format for Unicode strings, it considers this to be the natural encoding of Unicode tex...
Should I write script in the body or the head of the html? [duplicate]
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I would answer this with multiple options actually, the some of which actually render in the body.
Place library script such as the jQuery library in the head section.
Place normal script in the head unless it becomes a performance/page load issue.
Place script associa...
How to add a border just on the top side of a UIView
... return border
}
if edges.contains(.top) || edges.contains(.all) {
addBorder(formats: "V:|-0-[border(==thickness)]", "H:|-inset-[border]-inset-|")
}
if edges.contains(.bottom) || edges.contains(.all) {
addBorder(formats: "V:[border(==thickness)]-0-|", "H:|-ins...
What's onCreate(Bundle savedInstanceState)
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If you save the state of the application in a bundle (typically non-persistent, dynamic data in onSaveInstanceState), it can be passed back to onCreate if the activity needs to be recreated (e.g., orientation change) so that you don't lose this prior information. If no data was suppl...