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How to find a table having a specific column in postgresql
...attribute as a on a.attrelid = c.oid
where a.attname = <column name> and c.relkind = 'r'
sql fiddle demo
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Is using Random and OrderBy a good shuffle algorithm?
...t an O(n) shuffle. The code in the question "works" by basically giving a random (hopefully unique!) number to each element, then ordering the elements according to that number.
I prefer Durstenfield's variant of the Fisher-Yates shuffle which swaps elements.
Implementing a simple Shuffle extensio...
Does MySQL ignore null values on unique constraints?
...sult:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
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How to use GROUP_CONCAT in a CONCAT in MySQL
...ated) against a unique[Name,id]. Then from obtained table we get all names and values as a single value against each unique id
See this explained here SQL Fiddle Demo (scroll down as it has two result sets)
Edit There was a mistake in reading question, I had grouped only by id. But two group_contac...
Generating a random password in php
I am trying to generate a random password in php.
22 Answers
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Git status ignore line endings / identical files / windows & linux environment / dropbox / mled
...t setting on some work project. On work I must use windows, home I use mac and linux. Before this I had the same problem as you, after that setting everything was ok.
– Saša Šijak
Dec 12 '13 at 15:26
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Django - how to create a file and save it to a model's FileField?
Here's my model. What I want to do is generate a new file and overwrite the existing one whenever a model instance is saved:
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Breaking out of a nested loop
...nested within another, how can I efficiently come out of both loops (inner and outer) in the quickest possible way?
22 Answ...
Example images for code and mark-up Q&As [closed]
... in this answer. It includes a Java based interface that defines the URLs and makes them easy to access.
Details: 32x32 pixel PNG (4 colors x 5 shapes) with partial transparency (along the edges).
Categories: png icons
Sprite...
How to enter a multi-line command
Is it possible to split a PowerShell command line over multiple lines?
12 Answers
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