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How to add “on delete cascade” constraints?

... Based off of @Mike Sherrill Cat Recall's answer, this is what worked for me: ALTER TABLE "Children" DROP CONSTRAINT "Children_parentId_fkey", ADD CONSTRAINT "Children_parentId_fkey" FOREIGN KEY ("parentId") REFERENCES "P...
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Catching all javascript unhandled exceptions

... Check out http://log4javascript.org it is based on Log4J. If most of your code is wrapped in try/catch statements to handle exceptions you can make use of this library as a common interface for sending output to an always available "dialog box" or logging window that...
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Rails nested form with has_many :through, how to edit attributes of join model?

...ent for has_one and has_many associations. class User < ActiveRecord::Base has_one :profile has_many :messages end The build syntax for has_many association: user.messages.build The build syntax for has_one association: user.build_profile # this will work user.profile.build # this ...
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Why use a READ UNCOMMITTED isolation level?

...with read uncommitted on? Yes, in theory. You'll find no shortage of database architecture astronauts who start dropping ACID science on you and all but pull the building fire alarm when you tell them you want to try nolock. It's true: the theory is scary. But here's what I think: "In...
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EC2 instance types's exact network performance?

...mprehensive answer: For t2/m3/c3/c4/r3/i2/d2 instances: t2.nano = ??? (Based on the scaling factors, I'd expect 20-30 MBit/s) t2.micro = ~70 MBit/s (qiita says 63 MBit/s) - t1.micro gets about ~100 Mbit/s t2.small = ~125 MBit/s (t2, qiita says 127 MBit/s, cloudharmony says 125 Mbit/s with spikes...
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What is the difference between Cygwin and MinGW?

...for Windows. About Cygwin The purpose of Cygwin is to make porting Unix-based applications to Windows much easier, by emulating many of the small details that Unix-based operating systems provide, and are documented by the POSIX standards. Your application can use Unix feature such as pipes, Uni...
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What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]

... An SQL JOIN clause is used to combine rows from two or more tables, based on a common field between them. There are different types of joins available in SQL: INNER JOIN: returns rows when there is a match in both tables. LEFT JOIN: returns all rows from the left table, even if there are ...
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How do I script a “yes” response for installing programs?

...ing language). Expect is a language designed specifically to control text-based applications, which is exactly what you are looking to do. If you end up needing to do something more complicated (like with logic to actually decide what to do/answer next), Expect is the way to go. ...
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Setting git parent pointer to a different parent

... Using git rebase. It's the generic "take commit(s) and plop it/them on a different parent (base)" command in Git. Some things to know, however: Since commit SHAs involve their parents, when you change the parent of a given commit, its...
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Copying text to the clipboard using Java

... For JavaFx based applications. //returns System Clipboard final Clipboard clipboard = Clipboard.getSystemClipboard(); // ClipboardContent provides flexibility to store data in different formats final Cli...