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How do you determine what SQL Tables have an identity column programmatically
... edited Jan 23 '17 at 22:29
Mark Cidade
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answered Sep 17 '08 at 21:44
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What is cardinality in MySQL?
... called high-cardinality columns because they have constraints in place (like unique) prohibiting you from putting the same value in every row.
Cardinality is a property which affects the ability to cluster, sort and search data. It is therefore an important measurement for the query planners in D...
What does it mean to start a PHP function with an ampersand?
I'm using the Facebook library with this code in it:
3 Answers
3
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Understanding the ngRepeat 'track by' expression
I'm having difficulties understanding how the track by expression of ng-repeat in angularjs works. The documentation is very scarce: http://docs.angularjs.org/api/ng/directive/ngRepeat
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How do you clear a slice in Go?
...:
var slice []T
then enforcing len(slice) to be zero, by the above "trick", doesn't make any element of
slice[:cap(slice)]
eligible for garbage collection. This might be the optimal approach in some scenarios. But it might also be a cause of "memory leaks" - memory not used, but potentially r...
Can you use an alias in the WHERE clause in mysql?
I need to use an alias in the WHERE clause, but It keeps telling me that its an unknown column. Is there any way to get around this issue? I need to select records that have a rating higher than x. Rating is calculated as the following alias:
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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a_horse_with_no_name
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answered Jul 28 '09 at 14:30
hhaamuhhaamu
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Add missing dates to pandas dataframe
... data can have multiple events on a given date or NO events on a date. I take these events, get a count by date and plot them. However, when I plot them, my two series don't always match.
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how to add records to has_many :through association in rails
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I think you can simply do this:
@cust = Customer.new(params[:customer])
@cust.houses << House.find(params[:house_id])
Or when creating a new house for a customer:
@cust = Customer.new(params[:customer])
@cust.houses.c...
How to state in requirements.txt a direct github source
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“Editable” packages syntax can be used in requirements.txt to import packages from a variety of VCS (git, hg, bzr, svn):
-e git://github.com/mozilla/elasticutils.git#egg=elasticutils
Also, it is possible to point to particular commit:
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