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How do I add a foreign key to an existing SQLite table?
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SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as follows:
CREATE TABLE child (
id INTEGER PRIMARY KEY,
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Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
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How to display multiple notifications in android
I am receiving only one notification and if there comes another notification, it replaces the previous one and here is my code
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How to find duplicates in 2 columns not 1
...composite key between the two fields. This will require a unique stone_id and upcharge_title for each row.
As far as finding the existing duplicates try this:
select stone_id,
upcharge_title,
count(*)
from your_table
group by stone_id,
upcharge_title
having coun...
How do I access my SSH public key?
I've just generated my RSA key pair, and I wanted to add that key to GitHub.
18 Answers
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JavaScript and Threads
...ol API
WHATWG has a Draft Recommendation for worker threads: Web Workers
And there's also Mozilla’s DOM Worker Threads
Update: June 2009, current state of browser support for JavaScript threads
Firefox 3.5 has web workers. Some demos of web workers, if you want to see them in action:
Simu...
Can you pass parameters to an AngularJS controller on creation?
...al Answer:
I answered this to
Yes you absolutely can do so using ng-init and a simple init function.
Here is the example of it on plunker
HTML
<!DOCTYPE html>
<html ng-app="angularjs-starter">
<head lang="en">
<script src="//ajax.googleapis.com/ajax/libs/angularjs/1....
Reset auto increment counter in postgres
..._id_seq (that is, ${table}_${column}_seq).
This is the ALTER SEQUENCE command you need:
ALTER SEQUENCE product_id_seq RESTART WITH 1453
You can see the sequences in your database using the \ds command in psql. If you do \d product and look at the default constraint for your column, the nextval(....
Spring MVC: Complex object as GET @RequestParam
Suppose i have a page that lists the objects on a table and i need to put a form to filter the table. The filter is sent as an Ajax GET to an URL like that: http://foo.com/system/controller/action?page=1&prop1=x&prop2=y&prop3=z
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SQL query to find record with ID not in another table
I have two tables with binding primary key in database and I desire to find a disjoint set between them. For example,
6 Ans...