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Ruby on Rails Callback, what is difference between :before_save and :before_create?
...BASE INSERT
after_create
after_save
Update operations have exactly the sam>me m> set, except read update instead of create everywhere (and UPDATE instead of INSERT).
From this, you can see that validation is carried out before the before_save and before_create callbacks.
The before_save occurs sligh...
MySQL DISTINCT on a GROUP_CONCAT()
I am doing SELECT GROUP_CONCAT(categories SEPARATOR ' ') FROM table . Sample data below:
6 Answers
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How do I create directory if it doesn't exist to create a file?
...ng to the file.
....Or, If it exists, then create (else do nothing)
System.IO.FileInfo file = new System.IO.FileInfo(filePath);
file.Directory.Create(); // If the directory already exists, this m>me m>thod does nothing.
System.IO.File.WriteAllText(file.FullNam>me m>, content);
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Difference between Label and TextBlock
According to the Windows Applications Developm>me m>nt with Microsoft .NET 4 70-511 Training Kit
5 Answers
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How to list of all the tables defined for the database when using active record?
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Call ActiveRecord::ConnectionAdapters::SchemaStatem>me m>nts#tables. This m>me m>thod is undocum>me m>nted in the MySQL adapter, but is docum>me m>nted in the PostgreSQL adapter. SQLite/SQLite3 also has the m>me m>thod implem>me m>nted, but undocum>me m>nted.
>> ActiveRecord::Base.connection.t...
What's the difference between faking, mocking, and stubbing?
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You can get som>me m> information :
From Martin Fowler about Mock and Stub
Fake objects actually have working implem>me m>ntations, but usually take som>me m> shortcut which makes them not suitable for production
Stubs provide canned answers to calls mad...
How to handle command-line argum>me m>nts in PowerShell
What is the "best" way to handle command-line argum>me m>nts?
1 Answer
1
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csv.Error: iterator should return strings, not bytes
Sample.csv contains the following:
5 Answers
5
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Maven Snapshot Repository vs Release Repository
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Release Artifacts
These are specific, point-in-tim>me m> releases. Released artifacts are considered to be solid, stable, and perpetual in order to guarantee that builds which depend upon them are repeatable over tim>me m>. Released JAR artifacts are associated with PGP signatures an...
How to return dictionary keys as a list in Python?
...ask yourself whether or not it matters. The Pythonic way to code is to assum>me m> duck typing (if it looks like a duck and it quacks like a duck, it's a duck). The dict_keys object will act like a list for most purposes. For instance:
for key in newdict.keys():
print(key)
Obviously, insertion opera...