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Python: How would you save a simple settings/config file?

... reasons to use a different format. Write a file like so: # python 2.x # from ConfigParser import SafeConfigParser # config = SafeConfigParser() # python 3.x from configparser import ConfigParser config = ConfigParser() config.read('config.ini') config.add_section('main') config.set('main', 'key...
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How to randomly select rows in SQL?

... SELECT TOP 5 Id, Name FROM customerNames ORDER BY NEWID() That said, everybody seems to come to this page for the more general answer to your question: Selecting a random row in SQL Select a random row with MySQL: SELECT...
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How does a language expand itself? [closed]

... A computer is like an onion, it has many many layers, from the inner core of pure hardware to the outermost application layer. Each layer exposes parts of itself to the next outer layer, so that the outer layer may use some of the inner layers functionality. In the case of e.g....
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Using union and order by clause in mysql

...criteria from a table based on distance for a search on my site. The first select query returns data related to the exact place search . The 2nd select query returns data related to distance within 5 kms from the place searched. The 3rd select query returns data related to distance within 5-15 kms f...
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What is the difference between float and double?

...le gives 9.000000000000000066 on Mac), but all floating point types suffer from round-off errors, so if precision is very important (e.g. money processing) you should use int or a fraction class. Furthermore, don't use += to sum lots of floating point numbers, as the errors accumulate quickly. If y...
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Can you create nested WITH clauses for Common Table Expressions?

..., the form of the statement you are looking for would be WITH x AS ( SELECT * FROM MyTable ), y AS ( SELECT * FROM x ) SELECT * FROM y share | improve this answer | ...
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Best way to select random rows PostgreSQL

I want a random selection of rows in PostgreSQL, I tried this: 12 Answers 12 ...
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MySQL SELECT only not null values

Is it possible to do a select statement that takes only NOT NULL values? 9 Answers 9 ...
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sql query to return differences between two tables

...colum C, here are the records, which are present in table A but not in B: SELECT A.* FROM A LEFT JOIN B ON (A.C = B.C) WHERE B.C IS NULL To get all the differences with a single query, a full join must be used, like this: SELECT A.*, B.* FROM A FULL JOIN B ON (A.C = B.C) WHERE A.C IS NUL...
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What is Data URI support like in major email client software?

...hing like this is often very bad in email browsers. The issue really spans from many of them using their own cut down rendering engines that aren't full html renderers. In a system that it's still preferable to use a table based design to make sure emails are readable I wouldn't try to do anything c...