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Rails where condition using NOT NIL
...udes(:bar).where.not(bars: { id: nil })
When working with scopes between tables, I prefer to leverage merge so that I can use existing scopes more easily.
Foo.includes(:bar).merge(Bar.where.not(id: nil))
Also, since includes does not always choose a join strategy, you should use references here...
Select distinct values from a table field
...M. What I want to do is get a list of distinct values within a field on my table .... the equivalent of one of the following:
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Android Studio/Intellij Idea: “Table of Contents” for a class
...t I have seen. One thing that has been annoying me though is this lack of "Table of Contents" for a class. I apologize for not knowing exactly what to call it. But what I am referring to is the dropdown menu in eclipse that lists all the methods, interfaces, classes and so on that are in that class ...
When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
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GO is like the end of a script.
You could have multiple CREATE TABLE statements, separated by GO. It's a way of isolating one part of the script from another, but submitting it all in one block.
BEGIN and END are just like { and } in C/++/#, Java, etc.
They bound a logical block of ...
Debugging sqlite database on the device
... debuggable, you can use the shell run-as command to run a command or executable as a specific user/application or just switch to the UID of your application so you can access its data directory.
So if you wish to pull your application database from the device you should run the debug build of the...
Class with Object as a parameter
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In Python2 this declares Table to be a new-style class (as opposed to "classic" class).
In Python3 all classes are new-style classes, so this is no longer necessary.
New style classes have a few special attributes that classic classes lack.
class C...
SQLite - increase value by a certain number
is it possible to increase a certain value in a table by a certain number without reading last value and afterwards updating it?
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Joins are for lazy people?
...d that using joins is less efficient than making several requests and link tables in the code (C# or Java).
21 Answers
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onchange event on input type=range is not triggering in firefox while dragging
...ast either end of the slider
final mouse-up (or touch-end)
The following table shows how at least three different desktop browsers differ in their behaviour with respect to which of the above scenarios they respond to:
Solution:
The onRangeChange function provides a consistent and predictable ...
Unknown column in 'field list' error on MySQL Update query
...er inside single quotes; e.g.:
$name = "my name"
$query = " INSERT INTO mytable VALUES ( 1 , '$name') "
Note that although the query is enclosed between double quotes, you must enclose any string in single quotes.
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