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JPA getSingleResult() or null
...the query did not match any row or whether the query matched a row but the selected column contains null as its value. from: stackoverflow.com/a/12155901/1242321
– user1242321
Mar 16 '16 at 1:36
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How to break out from a ruby block?
...
def first_frog
detect {|i| i =~ /frog/ }
end
def last_frog
select {|i| i =~ /frog/ }.last
end
end
p ["dog", "cat", "godzilla", "dogfrog", "woot", "catfrog"].first_frog
# => "dogfrog"
p ["hats", "coats"].first_frog
# => nil
p ["houses", "frogcars", "bottles", "superfrogs"].la...
Get column index from column name in python pandas
...pecified label or are duplicates, the index with the larger index value is selected:
df = pd.DataFrame(
{"pear": [1, 2, 3], "apple": [2, 3, 4], "orange": [3, 4, 5]},
index=[0, .9, 1.1])
df.index.get_indexer([0, 1])
# array([ 0, -1], dtype=int64)
...
ruby 1.9: invalid byte sequence in UTF-8
...il if string.nil?
return string if string.valid_encoding?
string.chars.select { |c| c.valid_encoding? }.join
end
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Explanation of [].slice.call in javascript?
...'s being called from the parameter (the NodeList returned by document.querySelectorAll('a')) rather than from an array.
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How to update gradle in android studio?
...Build Tools→Gradle→Use default Gradle wrapper (recommended)
Step 2 (Select desired gradle version)
File→Project Structure→Project
The following table shows compatibility between Android plugin for Gradle and Gradle:
Latest stable versions you can use with Android Studio 4.0.1 (July 2020):...
Bower: ENOGIT Git is not installed or not in the PATH
...
Make sure you installed Git with the second or third option selected from the list. It will penetrate the Git command to cmd by modifying PATH automatically ;)
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How to make good reproducible pandas examples
...e a bit with np.random.choice. For example, in column g, we have a random selection of 6 dates from 2011. Additionally, by setting replace=False we can assure these dates are unique -- very handy if we want to use this as an index with unique values.
Fake stock market data
In addition to taking...
How to easily truncate an array with JavaScript?
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If you want to selectively pull elements out of an array, you can use the jQuery.grep method.
(from the jQuery docs)
var arr = [ 1, 9, 3, 8, 6, 1, 5, 9, 4, 7, 3, 8, 6, 9, 1 ];
$("div").text(arr.join(", "));
arr = jQuery.grep(arr, functi...
What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
... have to find the name used to index it. To find that, issue the following select:
SHOW CREATE TABLE region;
This should show you the name of the index, something like this:
CONSTRAINT region_ibfk_1 FOREIGN
KEY (country_id) REFERENCES
country (id) ON DELETE NO
ACTION ON UPDATE NO ACT...