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How to clone a case class instance and change just one field in Scala?
...ersonas, people on different social networks. Instances of that class are fully immutable, and are held in immutable collections, to be eventually modified by an Akka actor.
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MySQL SELECT WHERE datetime matches day (and not necessarily time)
I have a table which contains a datetime column. I wish to return all records of a given day regardless of the time. Or in other words, if my table only contained the following 4 records, then only the 2nd and 3rd would be returned if I limit to 2012-12-25.
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Is there a recommended format for multi-line imports?
I have read there are three ways for coding multi-line imports in python
4 Answers
4
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“unadd” a file to svn before commit
I was in the middle of doing a recursive svn add/commit, and a folder which did not have the proper ignore properties was included. I've got about 100 uploaded binary files versioned now, but I haven't committed yet.
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Eclipse Android and gitignore
What files/folders can I safely ignore for inclusion with git?
6 Answers
6
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What's the difference between lists enclosed by square brackets and parentheses in Python?
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Square brackets are lists while parentheses are tuples.
A list is mutable, meaning you can change its contents:
>>> x = [1,2]
>>> x.append(3)
>>> x
[1, 2, 3]
while tuples are not:
>>> x ...
Does MySQL ignore null values on unique constraints?
I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way?
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Why can't I center with margin: 0 auto?
I have a #header div that is 100% width and within that div I have an unordered list. I have applied margin: 0 auto to the unordered list but it won't center it within the header div.
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How do I calculate the normal vector of a line segment?
Suppose I have a line segment going from (x1,y1) to (x2,y2). How do I calculate the normal vector perpendicular to the line?
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sqlalchemy flush() and get inserted id?
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Your sample code should have worked as it is. SQLAlchemy should be providing a value for f.id, assuming its an autogenerating primary-key column. Primary-key attributes are populated immediately within the flush() process as t...