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Search for a string in Enum and return the Enum
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@user1531040 Actually, there is an Enum.TryParse.
– DarLom
Nov 1 '17 at 21:14
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Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSER...
AngularJS : Clear $watch
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$watch returns a deregistration function. Calling it would deregister the $watcher.
var listener = $scope.$watch("quartz", function () {});
// ...
listener(); // Would clear the watch
share
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How to get access to HTTP header information in Spring MVC REST controller?
I am new to web programming in general, especially in Java, so I just learned what a header and body is.
3 Answers
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Will Google Android ever support .NET? [closed]
... wondering, has there been any talk with Google to make this easier to install? Perhaps put it up as a free download from the Market? Allow .Net apps to be put on the market?
– csauve
Jun 2 '10 at 16:58
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How to disable a particular checkstyle rule for a particular line of code?
... <property name="checkFormat" value="$1"/>
</module>
which allows you to turn off specific checks for specific lines of code:
//CHECKSTYLE.OFF: IllegalCatch - Much more readable than catching 7 exceptions
catch (Exception e)
//CHECKSTYLE.ON: IllegalCatch
*Note: you'll also have to...
What's an object file in C?
...t from the compilation phase. It's mostly machine code, but has info that allows a linker to see what symbols are in it as well as symbols it requires in order to work. (For reference, "symbols" are basically names of global objects, functions, etc.)
A linker takes all these object files and comb...
What does ||= (or-equals) mean in Ruby?
...threads on the Ruby mailing-list whose only purpose is to collect links to all the other threads on the Ruby mailing-list that discuss this issue.
Here's one: The definitive list of ||= (OR Equal) threads and pages
If you really want to know what is going on, take a look at Section 11.4.2.3 "Abbrevi...
Jenkins Git Plugin: How to build specific tag?
... out to be critical. Although it seemed the git repositories were fetching all the remote information by default when I left it blank, the Git plugin would nevertheless completely fail to find my tag. Only when I explicitly specified "get the remote tags" in the Refspec field was the Git plugin able...
Difference between Key, Primary Key, Unique Key and Index in MySQL
...would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have t...