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How to select the nth row in a SQL database table?

...upports the standard windowing functions: SELECT * FROM ( SELECT ROW_NUMBER() OVER (ORDER BY key ASC) AS rownumber, columns FROM tablename ) AS foo WHERE rownumber <= n (which I just copied from the site linked above since I never use those DBs) Update: As of PostgreSQL 8.4 the st...
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Getting and removing the first character of a string

... x <- 'hello stackoverflow' substring(x, 2, nchar(x)) Idea is select all characters starting from 2 to number of characters in x. This is important when you have unequal number of characters in word or phrase. Selecting the first letter is trivial as previous answers: substring(x,1,1) ...
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Why does the MongoDB Java driver use a random number generator in a conditional?

...k && Math.random() <= 0.1) return res; The commit that originally introduced this logic had if (_ok == true) { _logger.log( Level.WARNING , "Server seen down: " + _addr, e ); } else if (Math.random() < 0.1) { _logger.log( Level.WARNING , "Server seen down: " + _addr ); } —a...
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Finding local IP addresses using Python's stdlib

... This example has an external dependency of being able to actually resolve gmail.com. If you set it to an ip address that is not on your local lan (doesn't matter if it's up or down) it'll work without dependencies and without network traffic. – grim ...
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Read environment variables in Node.js

...bles per project: Create a .env file under the project directory and put all of your variables there. Add this line in the top of your application entry file: require('dotenv').config(); Done. Now you can access your environment variables with process.env.ENV_NAME. ...
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MySQL Error 1153 - Got a packet bigger than 'max_allowed_packet' bytes

...port. For the client, you can specify it on the command line: mysql --max_allowed_packet=100M -u root -p database < dump.sql Also, change the my.cnf or my.ini file under the mysqld section and set: max_allowed_packet=100M or you could run these commands in a MySQL console connected to that...
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Using braces with dynamic variable names in PHP

I'm trying to use dynamic variable names (I'm not sure what they're actually called) But pretty much like this: 8 Answers ...
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How to do joins in LINQ on multiple fields in single join

...xplain that reason. If you want to do something other than what you originally asked for, please give an example of what you really want to do. EDIT: Responding to the edit in the question: yes, to do a "date range" join, you need to use a where clause instead. They're semantically equivalent real...
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Can I get JSON to load into an OrderedDict?

... I am perplexed. The docs say the object_pairs_hook gets called for each literal that gets decoded into pairs. Why doesn't this create a new OrderedDict for each record in the JSON? – Tim Keating Apr 25 '14 at 19:33 ...
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How to do multiple arguments to map function where one remains the same in python?

... @Shan: Very similar, especially if add() is a non-trivial function – Sven Marnach May 31 '12 at 13:52 2 ...