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How to convert a Map to List in Java?
...p<key,value> to a List<value> ? Just iterate over all values and insert them in a list or am I overlooking something?
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How to create a multi-tenant database with shared table structures?
...quires the use of more
sophisticated design patterns.
As for technical and business considerations, the article makes a brief analysis on where a certain approach might be more appropriate than another:
The number, nature, and needs of the
tenants you expect to serve all affect
your data...
How to get 0-padded binary representation of an integer in java?
...umbers to format, you can convert your binary representation to BigInteger and then format that with leading zeros, but this is very costly at runtime, as in:
String.format("%016d", new BigInteger(Integer.toBinaryString(1)))
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COUNT DISTINCT with CONDITIONS
... only positive values. Zeros or negative values would be evaluated as null and won't be included in count.
One thing to note here is that this can be done by reading the table once. When it seems that you have to read the same table twice or more, it can actually be done by reading once, in most of...
Angular.js: How does $eval work and why is it different from vanilla eval?
... $scope.$eval you so often see in directives, so I checked out the source and found the following in rootScope.js :
3 Ans...
Literal notation for Dictionary in C#?
I currently have a WebSocket between JavaScript and a server programmed in C#. In JavaScript, I can pass data easily using an associative array:
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How can I get nth element from a list?
...d have. So I think the idea was to allows it for edge cases, but make it stand out as non-idiomatic.
– cdosborn
Sep 26 '16 at 20:04
3
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Webstorm: “Cannot Resolve Directory”
This is starting to bug me and I'd either like it turned off or fixed. So Webstorm has a sweet feature in it's HTML parser that will attempt to resolve directories in strings that are supposed to reference a file in your project. For example:
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How to apply a function to two columns of Pandas dataframe
Suppose I have a df which has columns of 'ID', 'col_1', 'col_2' . And I define a function :
12 Answers
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What are the special dollar sign shell variables?
...shell (not subshell).
$_ most recent parameter (or the abs path of the command to start the current shell immediately after startup).
$IFS is the (input) field separator.
$? is the most recent foreground pipeline exit status.
$! is the PID of the most recent background command.
$0 is the name of the...