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How big is too big for a PostgreSQL table?
I'm working on the design for a RoR project for my company, and our development team has already run into a bit of a debate about the design, specifically the database.
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Combining INSERT INTO and WITH/CTE
I have a very complex CTE and I would like to insert the result into a physical table.
3 Answers
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Mozilla PDF.js：PDF在线预览 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ent Format(PDF) viewer that is built with HTML5.PDF.js is community-driven and supportedby Mozilla Labs. Our goal is to create a general-purpose, web standards-basedplatform for parsing and rendering PDFs.
PDF.js是一个由HTML5建立的PDF阅读器。依托开源社区驱动和Mozilla实验室的...
What is scope/named_scope in rails?
I've recently started an internship. My employer uses ruby on rails, and I frequently encounter new syntax that I need to look up to understand. I've googled around for a good explanation of named_scope, but what I've found so far is mostly blog posts giving high praise for it, rather a straight def...
Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between print (x) and print (x, ...
Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
Every time I mention slow performance of C++ standard library iostreams, I get met with a wave of disbelief. Yet I have profiler results showing large amounts of time spent in iostream library code (full compiler optimizations), and switching from iostreams to OS-specific I/O APIs and custom buffer...
Postgres: Distinct but only for one column
...d catch on ordering. I didn't include it because they mentioned wanting a random ordering, but it's important to mention anyway.
– Craig Ringer
Jun 4 '13 at 12:49
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CoffeeScript, When to use fat arrow (=>) over arrow (->) and vice versa
...ll the instance method be defined using the => ("fat arrow") operator and all the static methods being defined using the -> operator?
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COUNT DISTINCT with CONDITIONS
... only positive values. Zeros or negative values would be evaluated as null and won't be included in count.
One thing to note here is that this can be done by reading the table once. When it seems that you have to read the same table twice or more, it can actually be done by reading once, in most of...
Django - Difference between import django.conf.settings and import settings
...ings file. django.conf.settings abstracts the concepts of default settings and site-specific settings; it presents a single interface. It also decouples the code that uses settings from the location of your settings.
UPDATE: if you want to define some own settings, see this part of the documentati...