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How do I create a unique constraint that also allows nulls?
...Ls are not...
In SQL Server 2008, you can define a unique filtered index based on a predicate that excludes NULLs:
CREATE UNIQUE NONCLUSTERED INDEX idx_yourcolumn_notnull
ON YourTable(yourcolumn)
WHERE yourcolumn IS NOT NULL;
In earlier versions, you can resort to VIEWS with a NOT NULL predicat...
How to deserialize a list using GSON or another JSON library in Java?
...ss AbstractList and doesn't override the method remove(int index) from the base class. And if you look at the source code of the AbstractList.remove(int index) you would see it always thrown UnsupportedOperationException. The same is for add() method.
– Bogdan Kornev
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How to set RelativeLayout layout params in code not in xml?
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There is no such thing like LayoutParams. The base class is actually ViewGroup.LayoutParams. If you want it shorter, just add an import that includes RelativeLayout.LayoutParams.
– Cristian
Nov 17 '12 at 17:13
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setNeedsLayout vs. setNeedsUpdateConstraints and layoutIfNeeded vs updateConstraintsIfNeeded
...before the animation manually, and the animation only re-lays-out the view based on differences between the old and new ones.
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How do I automatically update a timestamp in PostgreSQL
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Updating timestamp, only if the values changed
Based on E.J's link and add a if statement from this link (https://stackoverflow.com/a/3084254/1526023)
CREATE OR REPLACE FUNCTION update_modified_column()
RETURNS TRIGGER AS $$
BEGIN
IF row(NEW.*) IS DISTINCT FROM row(OL...
What is this CSS selector? [class*=“span”]
... 2's scaffolding technique which divided a section into a horizontal grid, based on parts of 12. Thus span6 would have a width of 50%.
In the current day implementation of Bootstrap (v.3 and v.4), you now use the .col-* classes (e.g. col-sm-6), which also specifies a media breakpoint to handle resp...
How can I add remote repositories in Mercurial?
... server repository from Mercurial.
This means you can collaborate on Git based projects from Mercurial, or use a Git server as a collaboration point for a team with developers using both Git and Mercurial.
Note: I haven't tested that tool with the latest versions of Mercurial.
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Async/Await vs Threads
...sing back to - you guessed it - the main thread. Think of it like an event based GOTO statement in Basic that can pass control back and forth to a specific line of execution.
In contrast a thread is a separate stream of execution that can run with its own variables etc. where - given sufficient har...
XML attribute vs XML element
...ose. I would have done something like:
EDIT: Updated the original example based on feedback below.
<ITEM serialNumber="something">
<BARCODE encoding="Code39">something</BARCODE>
<LOCATION>XYX</LOCATION>
<TYPE modelNumber="something">
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How does JavaFX compare to WPF? [closed]
...d colours which is useful for creating things like gradients. This means a base palette of colours can be defined and the rest can be generated from these values (this is what the default JavaFX CSS file does).
JavaFX CSS does not allow you to define the type of layout used by a node (as of writing...