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How to count the number of occurrences of an element in a List
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22 Answers
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Decode HTML entities in Python string?
... 3.4+
Use html.unescape():
import html
print(html.unescape('£682m'))
FYI html.parser.HTMLParser.unescape is deprecated, and was supposed to be removed in 3.5, although it was left in by mistake. It will be removed from the language soon.
Python 2.6-3.3
You can use HTMLParser.unesca...
Rails check if yield :area is defined in content_for
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217
@content_for_whatever is deprecated.
Use content_for? instead, like this:
<% if content_fo...
Why are there two build.gradle files in an Android Studio project?
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2 Answers
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Why are C# 3.0 object initializer constructor parentheses optional?
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This question was the subject of my blog on September 20th 2010. Josh and Chad's answers ("they add no value so why require them?" and "to eliminate redundancy") are basically correct. To flesh that out a bit more:
The feature of allowing you to elide the argument list as part ...
@UniqueConstraint annotation in Java
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427
To ensure a field value is unique you can write
@Column(unique=true)
String username;
The @U...
What is cardinality in MySQL?
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122
Max cardinality: All values are unique
Min cardinality: All values are the same
Some columns ...
See my work log in jira
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edited Sep 6 '16 at 22:43
Nathron
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Check if list contains element that contains a string and get that element
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12 Answers
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Create PostgreSQL ROLE (user) if it doesn't exist
...TABLE there is no IF NOT EXISTS clause for CREATE ROLE (up to at least pg 12). And you cannot execute dynamic DDL statements in plain SQL.
Your request to "avoid PL/pgSQL" is impossible except by using another PL. The DO statement uses plpgsql as default procedural language. The syntax allows to om...