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Random record in ActiveRecord
...he first, all after are still sorted by id). If you need multiple randomly selected records you must use this approach multiple times or use the random order method provided by your database, i.e. Thing.order("RANDOM()").limit(100) for 100 randomly selected entries. (Be aware that it's RANDOM() in P...
How to find duplicates in 2 columns not 1
..._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 count(*) > 1
...
Bad class file magic or version
... an Android SDK you should specify at which SDK you refer... (In my case I selected Java 7 because I was using this version) But it depends in your case too. Search online for other errors with the same name, you'll find a lot of information
– Marco Acierno
Jan...
Select2 dropdown but allow new values by user?
I want to have a dropdown with a set of values but also allow the user to "select" a new value not listed there.
9 Answers...
Throwing the fattest people off of an overloaded airplane.
...uch better. I use something quite like this for a recommendation engine (I select the top 200 items from a list of several million). I typically end up with only 50,000 or 70,000 items actually added to the heap.
I suspect that you'll see something quite similar: the majority of your candidates wil...
Find all elements on a page whose element ID contains a certain text using jQuery
... $(this).doStuff();
});
Note the asterisk '*' at the beginning of the selector matches all elements.
See the Attribute Contains Selectors, as well as the :visible and :hidden selectors.
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Better way of incrementing build number?
...ersion number (only) when a project is archived for export.
# @usage
# 1. Select: your Target in Xcode
# 2. Select: Build Phases Tab
# 3. Select: Add Build Phase -> Add Run Script
# 4. Paste code below in to new "Run Script" section
# 5. Check the checkbox "Run script only when installing"
# 6. ...
SQL-Server: The backup set holds a backup of a database other than the existing
...go for the restore option
Under Options on the left pane don't forget to select
Overwrite the existing database
Preserve the replication settings
That's it
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Ignoring time zones altogether in Rails and PostgreSQL
...n parameter before being displayed to the client.
Example (in psql):
db=# SELECT timestamptz '2012-03-05 20:00+03';
timestamptz
------------------------
2012-03-05 18:00:00+01
What happened here?
I chose an arbitrary time zone offset +3 for the input literal. To Postgres, this is just one o...
HTML5 Canvas vs. SVG vs. div
...ample, let's say I want to create a rectangle, circle and polygon and then select those objects and move them around.
8 Ans...