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How to get multiple counts with one SQL query?
...a.distributor_id,
(SELECT COUNT(*) FROM myTable WHERE level='personal' and distributor_id = a.distributor_id) as PersonalCount,
(SELECT COUNT(*) FROM myTable WHERE level='exec' and distributor_id = a.distributor_id) as ExecCount,
(SELECT COUNT(*) FROM myTable WHERE distributor_id = a.dis...
How do you run multiple programs in parallel from a bash script?
...t prog1.
Send it to background, but keep printing its output.
Start prog2, and keep it in foreground, so you can close it with ctrl-c.
When you close prog2, you'll return to prog1's foreground, so you can also close it with ctrl-c.
...
Databinding an enum property to a ComboBox in WPF
...L:
xmlns:my="clr-namespace:namespace_to_enumeration_extension_class
and then...
<ComboBox
ItemsSource="{Binding Source={my:Enumeration {x:Type my:Status}}}"
DisplayMemberPath="Description"
SelectedValue="{Binding CurrentStatus}"
SelectedValuePath="Value" />
And...
Changing MongoDB data store directory
Until now I have not been specifying a MongoDB data directory and have had only one 30 GB primary partition.
9 Answers
...
Test if string is a number in Ruby on Rails
...method:
def is_number? string
true if Float(string) rescue false
end
And then call it like this:
my_string = '12.34'
is_number?( my_string )
# => true
Extend String Class.
If you want to be able to call is_number? directly on the string instead of passing it as a param to your helper f...
Way to read first few lines for pandas dataframe
...e lines ahead of time? I have a large file that takes a long time to read, and occasionally only want to use the first, say, 20 lines to get a sample of it (and prefer not to load the full thing and take the head of it).
...
How can I update a single row in a ListView?
...ave a ListView which displays news items. They contain an image, a title and some text. The image is loaded in a separate thread (with a queue and all) and when the image is downloaded, I now call notifyDataSetChanged() on the list adapter to update the image. This works, but getView() is gett...
Favorite (Clever) Defensive Programming Best Practices [closed]
...ensive coding, what would they be? Although my current languages are Java and Objective-C (with a background in C++), feel free to answer in any language. Emphasis here would be on clever defensive techniques other than those that 70%+ of us here already know about. So now it is time to dig dee...
How to assign a heredoc value to a variable in Bash?
...
You can avoid a useless use of cat and handle mismatched quotes better with this:
$ read -r -d '' VAR <<'EOF'
abc'asdf"
$(dont-execute-this)
foo"bar"''
EOF
If you don't quote the variable when you echo it, newlines are lost. Quoting it preserves them:...
Matplotlib connect scatterplot points with line - Python
I have two lists, dates and values. I want to plot them using matplotlib. The following creates a scatter plot of my data.
...