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How do I join two SQLite tables in my Android application?
I have an Android project that has a database with two tables: tbl_question and tbl_alternative .
4 Answers
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SQL SELECT speed int vs varchar
I'm in the process of creating a table and it made me wonder.
9 Answers
9
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Can I restore deleted files (undo a `git clean -fdx`)?
I was following the instructions on making github pages , and forgot to move down into my git sub directory. As a result, I just nuked an entire directory of documents with git clean -fdx .
Is there any way I can undo this terrible mistake?
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Operator overloading in Java
... aspect of Java which comes close to "custom" operator overloading is the handling of + for strings, which either results in compile-time concatenation of constants or execution-time concatenation using StringBuilder/StringBuffer. You can't define your own operators which act in the same way though....
Why are interface variables static and final by default?
Why are interface variables static and final by default in Java?
15 Answers
15
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Split array into chunks
...his answer):
More efficient method:
// refresh page if experimenting and you already defined Array.prototype.chunk
Object.defineProperty(Array.prototype, 'chunk', {
value: function(chunkSize) {
var R = [];
for (var i = 0; i < this.length; i += chunkSize)
R.push(this.s...
How to test if a string is basically an integer in quotes using Ruby
...!!(str =~ /^[-+]?[0-9]+$/) would do that. Then you could add it to String and leave out the argument, using "self" instead of "str", and then you could change the name to "is_i?" ...
– janm
Aug 5 '09 at 22:16
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How to print out all the elements of a List in Java?
...odels = new ArrayList<>();
// TODO: First create your model and add to models ArrayList, to prevent NullPointerException for trying this example
// Print the name from the list....
for(Model model : models) {
System.out.println(model.getName());
}
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Rotating a point about another point (2D)
...onizer exactly the same, just use your point subtraction/addition routines and your vector*matrix function for rotation.
– Nils Pipenbrinck
Oct 2 '17 at 4:37
8
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Many-to-many relationship with the same model in rails?
...documentation on the subject. There's a section called “Many-to-many”, and of course the documentation on the class methods themselves.
Simplest scenario, uni-directional, no additional fields
This is the most compact in code.
I'll start out with this basic schema for your posts:
create_tabl...