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SQL JOIN and different types of JOINs
...gt;, < or BETWEEN etc. For implementation see INNER-JOIN.
Self-Join:: A customized behavior of join where a table combined with itself; This is typically needed for querying self-referencing tables (or Unary relationship entity).
For implementation see INNER-JOINs.
Cartesian Product: It cross com...
What's the easy way to auto create non existing dir in ansible
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To ensure success with a full path use recurse=yes
- name: ensure custom facts directory exists
file: >
path=/etc/ansible/facts.d
recurse=yes
state=directory
share
|
...
How to clear the cache in NetBeans
...ally there -- the class with the main method was not being found, and some custom exception classes were not being recognized as implementing Throwable... I just deleted the stupid cache, and now all of it works fine.
– Ian Campbell
Sep 20 '13 at 0:59
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What is the most efficient/elegant way to parse a flat table into a tree?
...Closure Table in my presentation Models for Hierarchical Data with SQL and PHP and in my book SQL Antipatterns: Avoiding the Pitfalls of Database Programming.
CREATE TABLE ClosureTable (
ancestor_id INT NOT NULL REFERENCES FlatTable(id),
descendant_id INT NOT NULL REFERENCES FlatTable(id),
...
Use rvmrc or ruby-version file to set a project gemset with RVM?
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If your .rvmrc file contains custom shell code, continue using .rvmrc as it allows you to include any shell code.
If your only aim is to switch Ruby versions, then use .ruby-version which is supported by other Ruby version switchers such as rbenv or chr...
What's the best way to use R scripts on the command line (terminal)?
...ten than not Bash is outdated on compute clusters and users have their own custom installations (commonly in ~/.local/bin, or shared in something like a /software NFS mount). Likewise, on macOS, /bin/bash is always outdated due to licensing issues, and an up to date Bash is more commonly located at ...
How can you tell when a layout has been drawn?
I have a custom view that draws a scrollable bitmap to the screen. In order to initialize it, i need to pass in the size in pixels of the parent layout object. But during the onCreate and onResume functions, the Layout has not been drawn yet, and so layout.getMeasuredHeight() returns 0.
...
Android soft keyboard covers EditText field
...Floating">true</item> in your dialog style, in case you are using custom dialog style.
– Dmitry Chistyakov
Jan 28 '13 at 12:34
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How to have an automatic timestamp in SQLite?
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you can use the custom datetime by using...
create table noteTable3
(created_at DATETIME DEFAULT (STRFTIME('%d-%m-%Y %H:%M', 'NOW','localtime')),
title text not null, myNotes text not null);
use 'NOW','localtime' to get the current...
ActiveModel::ForbiddenAttributesError when creating new user
...oad_and_authorize_resource can now take a param_method option to specify a custom method in the controller to run to sanitize input.
You can associate the param_method option with a symbol corresponding to the name of a method that will get called:
class ArticlesController < ApplicationControll...