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Possible to do a MySQL foreign key to one of two possible tables?
...table.
Polymorphic Associations are supported by frameworks such as Rails and Hibernate. But they explicitly say that you must disable SQL constraints to use this feature. Instead, the application or framework must do equivalent work to ensure that the reference is satisfied. That is, the value ...
How to resolve “local edit, incoming delete upon update” message
...nflict is about directories instead of files then replace touch with mkdir and rm with rm -r.
Note: the same procedure also work for the following situation:
$ svn st
! C foo
> local delete, incoming delete upon update
! C bar
> local delete, incoming delete upon up...
How to implement onBackPressed() in Fragments?
Is there a way in which we can implement onBackPressed() in Android Fragment similar to the way in which we implement in Android Activity?
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PersistentObjectException: detached entity passed to persist thrown by JPA and Hibernate
... to the corresponding getters. A big word of caution is not to mix "Field" and "Property" access types within the entity class otherwise the behavior is undefined by the JSR-317 specifications.
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How to calculate time difference in java?
...ariables won't do much good.. In this example, sure, you could invert them and take the absolute value or something. But what happens if you have midnight (00:00)?
– rj2700
Feb 20 '17 at 23:00
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What Every Programmer Should Know About Memory?
... fundamental concepts about memory: how CPU cache works, what are physical and virtual memory and how Linux kernel deals that zoo. Probably there are outdated API references in some examples, but it doesn't matter; that won't affect the relevance of the fundamental concepts.
So, any book or article...
Truncating all tables in a Postgres database
... SELECT tablename FROM pg_tables
WHERE tableowner = username AND schemaname = 'public';
BEGIN
FOR stmt IN statements LOOP
EXECUTE 'TRUNCATE TABLE ' || quote_ident(stmt.tablename) || ' CASCADE;';
END LOOP;
END;
$$ LANGUAGE plpgsql;
This creates a stored function (you n...
Using success/error/finally/catch with Promises in AngularJS
I'm using $http in AngularJs, and I'm not sure on how to use the returned promise and to handle errors.
6 Answers
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Print Current Mercurial Revision Hash?
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No prob. hg help revisions and hg help revsets has some crazy powerful shortcuts like that.
– Ry4an Brase
Jun 13 '12 at 20:47
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How to pipe stdout while keeping it on screen ? (and not to a output file)
I would like to pipe standard output of a program while keeping it on screen.
5 Answers
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