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Simple Pivot Table to Count Unique Values
This seems like a simple Pivot Table to learn with. I would like to do a count of unique values for a particular value I'm grouping on.
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Only using @JsonIgnore during serialization, but not deserialization
.... So, I added @JsonIgnore on the password property, but this also blocks it from being deserialized into the password that makes it hard to sign up users when they ain't got a password.
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Why were pandas merges in python faster than data.table merges in R in 2012?
... which according to this benchmark performs very fast in-memory merges. It's even faster than the data.table package in R (my language of choice for analysis).
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Android LinearLayout : Add border with shadow around a LinearLayout
...ist xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape android:shape="rectangle">
<solid android:color="#CABBBBBB"/>
<corners android:radius="2dp" />
</shape>
</item>
<item
a...
Number of rows affected by an UPDATE in PL/SQL
...w many rows were affected by the UPDATE? When executing the query manually it tells me how many rows were affected, I want to get that number in PL/SQL.
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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C# Sortable collection which allows duplicate keys
I am writing a program to set a sequence in which various objects will appear in report.
The sequence is the Y position (cell) on Excel spreadsheet.
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Difference between == and ===
In swift there seem to be two equality operators: the double equals ( == ) and the triple equals ( === ), what is the difference between the two?
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When converting a project to use ARC what does “switch case is in protected scope” mean?
When converting a project to use ARC what does "switch case is in protected scope" mean?
I am converting a project to use ARC, using Xcode 4 Edit -> Refactor -> Convert to Objective-C ARC...
One of the errors I get is "switch case is in protected scope" on "some" of the switches in a switch case.
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How can I selectively escape percent (%) in Python strings?
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>>> test = "have it break."
>>> selectiveEscape = "Print percent %% in sentence and not %s" % test
>>> print selectiveEscape
Print percent % in sentence and not have it break.
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