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Rails where condition using NOT NIL
..., so you really should just use the joins predicate:
Foo.joins(:bar)
Select * from Foo Inner Join Bars ...
But, for the record, if you want a "NOT NULL" condition simply use the not predicate:
Foo.includes(:bar).where.not(bars: {id: nil})
Select * from Foo Left Outer Join Bars on .. WHERE ...
“Java DateFormat is not threadsafe” what does this leads to?
...eFormat object and called its format() for values read via JDBC. I had SQL select statement where I read the same date with different names (SELECT date_from, date_from AS date_from1 ...). Such statements were using in 5 threads for various dates in WHERE clasue. Dates looked "normal" but they diffe...
Sublime Text 3, convert spaces to tabs
... And this does on the entire file, and can not be done only on a selection.
– not2qubit
Jan 8 '18 at 17:55
...
Configuring IntelliJ IDEA for unit testing with JUnit
...or or by using Ctrl+Shift+T keyboard shortcut.
A dialog appears where you select what testing framework to use and press Fix button for the first time to add the required library jars to the module dependencies. You can also select methods to create the test stubs for.
You can find more detail...
Is there a use-case for singletons with database access in PHP?
...all one needs to maintain multiple database connections, multiple database selections, multiple database queries, multiple result sets in a given singleton is just keeping them in variables/arrays in the singleton as long as they are needed. This can be as simple as keeping them in arrays, though yo...
Using NumberPicker Widget with Strings
...wrap true or false, try it you will know the difference
pickers.setWrapSelectorWheel(false);
//create button to test selected text string
btnPicker.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//get position (int)...
Input placeholders for Internet Explorer
...n(){
if (input.val() === text) input.css({ color:'lightGrey' }).selectRange(0,0).one('keydown', function(){
input.val("").css({ color:'black' });
});
});
input.blur(function(){
if (input.val() == "" || input.val() === text) input.val(text)...
Difference between binary semaphore and mutex
...perspective, mutex are more like state-pattern where the algorithm that is selected by the state can change the state. The binary-semaphore are more like strategy pattern where the external algorithm can change the state and eventually the algorithm/strategy selected to run.
– ...
How can I use Google's Roboto font on a website?
...gle's Web Fonts page
search for Roboto in the search box at the top right
Select the variants of the font you want to use
click 'Select This Font' at the top and choose the weights and character sets you need.
The page will give you a <link> element to include in your pages, and a list of s...
What do the arrow icons in Subclipse mean?
... the following buttons:
- Synchronizes the local copy with the currently selected repository when clicked. Selecting from the drop-down allows switching between different remote code bases.
- Shows only incoming changes (remote → local).
- Shows only outgoing changes (local → remote).
- Sho...