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How To Create Table with Identity Column
...'s specific situation, would be to edit the one line in the generated DDL, and not try to write it from scratch using simplest syntax. Also the example you gave does not assign a name to the PK constraint as OP has. Many prefer my constraints named so they have the same name in all environments (dev...
Select rows which are not present in other table
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There are basically 4 techniques for this task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
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How can I create a Set of Sets in Python?
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Python's complaining because the inner set objects are mutable and thus not hashable. The solution is to use frozenset for the inner sets, to indicate that you have no intention of modifying them.
share
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What is a tracking branch?
...a direct relationship to a remote branch. If you’re on a tracking branch and type git push, Git automatically knows which server and branch to push to. Also, running git pull while on one of these branches fetches all the remote references and then automatically merges in the corresponding remote ...
What is the IntelliJ shortcut key to create a javadoc comment?
In Eclipse, I can press Alt + Shift + J and get a javadoc comment automatically generated with fields, returns, or whatever would be applicable for that specific javadoc comment. I'm assuming that IntelliJ IDEA has this feature. Can anyone tell me if there is a keyboard shortcut for this?
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Convert Time from one time zone to another in Rails
... created_at.in_time_zone("EST") is shorter
– Orlando
Jun 14 '12 at 18:00
51
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What column type/length should I use for storing a Bcrypt hashed password in a Database?
...password (using BCrypt) in a database. What would be a good type for this, and which would be the correct length? Are passwords hashed with BCrypt always of same length?
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Reference assignment operator in PHP, =&
What does the =& (equals-ampersand) assignment operator do in PHP?
4 Answers
4
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How to handle command-line arguments in PowerShell
What is the "best" way to handle command-line arguments?
1 Answer
1
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Change x axes scale in matplotlib
... is it possible to add an offset? (e.g. instead of 0.0, 0.5, 1.0, 1.5, ... and x 10^b it will be 0, 5, 10, 15,... and x 10^{b-1})
– Eagle
Jul 20 '12 at 13:20
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