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When and why are database joins expensive?
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Denormalising to improve performance? It sounds convincing, but it doesn't hold water.
Chris Date, who in company with Dr Ted Codd was the original proponent of the relational data model, ran out of patience with misinformed argumen...
Why is there no xrange function in Python3?
...len=0)
1 loops, best of 3: 1.33 s per loop
Apparently, 3.x range really is a bit slower than 2.x xrange. And the OP's xrange function has nothing to do with it. (Not surprising, as a one-time call to the __iter__ slot isn't likely to be visible among 10000000 calls to whatever happens in the loop...
MySQL: selecting rows where a column is null
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SQL NULL's special, and you have to do WHERE field IS NULL, as NULL cannot be equal to anything,
including itself (ie: NULL = NULL is always false).
See Rule 3 https://en.wikipedia.org/wiki/Codd%27s_12_rules
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How to use bootstrap-theme.css with bootstrap 3?
...e pack of bootstrap 3 from http://getbootstrap.com , I noticed that there is a separate css file for theme. How to make use of it? Please explain?
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Node.js or Erlang
...you will be learning a functional programming language. Also, since Erlang is specifically designed to create reliable, highly concurrent systems, you will learn plenty about creating highly scalable services at the same time.
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How do I unlock a SQLite database?
How do I unlock the database so this will work?
35 Answers
35
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What is REST? Slightly confused [closed]
...that REST was a web service but it seems that I am incorrect in thinking this - so, what is REST?
5 Answers
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Deleting a resource using http DELETE
So, given that the DELETE verb in Http is idempotent, when I issue the following request, what should happen the second (or third, or fourth, etc...)?
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reStructuredText tool support
...s that support it are scattered all over the Internet. The official tool list is incomplete and/or outdated, and can be updated only via commit privileges. For some time there was a comprehensive list at the Wikipedia reStructuredText page , but this apparently " did not meet the notability guide...
Is it safe to delete a NULL pointer?
Is it safe to delete a NULL pointer?
7 Answers
7
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