大约有 47,000 项符合查询结果（耗时：0.0505秒） [XML]
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
How to check size of a file using Bash?
... be an easier way to check for file sizes instead. I.e. file.txt is normally 100k; how to make a script check if it is less than 90k (including 0), and make it do wget a new copy because the file is corrupt in this case.
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Get selected subcommand with argparse
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answered Jan 1 '11 at 21:10
robertrobert
27.8k88 gold badges5050 silver badges7070 bronze badges
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What does `someObject.new` do in Java?
... And, as you can tell, this can be incredibly confusing. Ideally, inner classes should be implementation details of the outer class and not be exposed to the outside world.
– Eric Jablow
Mar 30 '13 at 23:45
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Unicode equivalents for \w and \b in Java regular expressions?
...cter class shorthand as "any letter, digit, or connecting punctuation" (usually: underscore). That way, a regex like \w+ matches words like hello , élève , GOÄ_432 or gefräßig .
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Permission denied (publickey) when deploying heroku code. fatal: The remote end hung up unexpectedly
...If you don't have a public key, Heroku will prompt you to add one automatically which works seamlessly. Just use:
heroku keys:add
To clear all your previous keys do :
heroku keys:clear
To display all your existing keys do :
heroku keys
EDIT:
The above did not seem to work for me. I had me...
Python Threading String Arguments
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answered Jul 11 '10 at 2:54
StephenStephen
40.9k77 gold badges5656 silver badges6767 bronze badges
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What column type/length should I use for storing a Bcrypt hashed password in a Database?
... I don't get the reason why I should bother about binary or not binary at all, if I don't want to sort by password hash, compare hashes on database layer or make the password column unique (“Sorry, this password is already in use”) at all. I'd recommend using UTF8 everywhere. In that case there...
How to check if object (variable) is defined in R?
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heh. Happens to me all the time when I am testing out examples before posting, Gavin or Josh have already answered it.
– Maiasaura
Feb 20 '12 at 22:17
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Converting unix timestamp string to readable date
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Steven Kryskalla
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answered Sep 10 '10 at 7:09
Michał NiklasMichał N...