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Insert into … values ( SELECT … FROM … )

...SERT from another table I did the following in SQLite3: INSERT INTO column_1 ( val_1, val_from_other_table ) VALUES('val_1', (SELECT val_2 FROM table_2 WHERE val_2 = something)) share | improve ...
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What are some (concrete) use-cases for metaclasses?

...ate methods, than to do something like: class PlottingInteractive: add_slice = wrap_pylab_newplot(add_slice) This method doesn't keep up with API changes and so on, but one that iterates over the class attributes in __init__ before re-setting the class attributes is more efficient and keeps t...
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What is the difference between JSON and Object Literal Notation?

...t console.log('Object Literal : ', objLiteral ); // Object {foo: 42}foo: 42__proto__: Object // This is a JSON String, like what you'd get back from an AJAX request. var jsonString = '{"foo": 452}'; console.log('JOSN String : ', jsonString ); // {"foo": 452} // This is how you deserialize that JSO...
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How to drop all tables in a SQL Server database?

...ECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR SET @Cursor = CURSOR FAST_FORWARD FOR SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];' FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1 LEFT JOIN INFORMATION_SCHEMA.TABLE_...
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What is the Scala annotation to ensure a tail recursive function is optimized?

...e to Scala version 2.8.0.RC5 (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_18). Type in expressions to have them evaluated. Type :help for more information. scala> import scala.annotation.tailrec import scala.annotation.tailrec scala> class Tails { | @tailrec def boom(x: Int): Int = { ...
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Using the HTML5 “required” attribute for a group of checkboxes?

...="checkbox-group required"> <input type="checkbox" name="checkbox_name[]"> <input type="checkbox" name="checkbox_name[]"> <input type="checkbox" name="checkbox_name[]"> <input type="checkbox" name="checkbox_name[]"> </div> You can use this expressio...
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Pass ruby script file to rails console

... You can use bundle exec rails runner "eval(File.read 'your_script.rb')" UPDATE: What we also have been using a lot lately is to load the rails environment from within the script itself. Consider doit.rb: #!/usr/bin/env ruby require "/path/to/rails_app/config/environment" # ......
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Breakpoint on property change

...al object var obj = { someProp: 10 }; // save in another property obj._someProp = obj.someProp; // overwrite with accessor Object.defineProperty(obj, 'someProp', { get: function () { return obj._someProp; }, set: function (value) { debugger; // sets breakpoint ...
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Immutability of Strings in Java

...lease? That will make my understanding clear. – Light_handle Oct 12 '09 at 17:30 17 I've never se...
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Bad class file magic or version

... my JAVA_HOME variable changed to Java 1.8 and I got this error message when compiling a pure java module as a dependency of my android project. build.gradle of the java module apply plugin: 'java' Solution #1: Quick an dirty I ...