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LEFT JOIN only first row
... Thanks for your fast response. This was not the exact answer, but totally got me on the right way. I always tried to join both on the same level instead of making the one depended from the other. Thank you very much for leading me on the right track. Edited the first post
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How to get the original value of an attribute in Rails
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Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should ap...
When to use ' (or quote) in Lisp?
...al operator (quote) (or equivalent ' ) function does, yet this has been all over Lisp code that I've seen.
10 Answers
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When is -XAllowAmbiguousTypes appropriate?
... should be able to follow functional dependencies in order to disambiguate all the other types used in the context, namely sup and fi. And indeed, the f -> internal functional dependency in SyntacticN uses our f to disambiguate our fi, and thereafter the f -> sig sym functional dependency in A...
How do I calculate tables size in Oracle
Being used to (and potentially spoiled by) MSSQL, I'm wondering how I can get at tables size in Oracle 10g.
I have googled it so I'm now aware that I may not have as easy an option as sp_spaceused. Still the potential answers I got are most of the time outdated or don't work. Probably because I'm no...
“Auto Layout still required after executing -layoutSubviews” with UITableViewCell subclass
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I encountered the same problem while manually adding constraints in code. In code, I was doing the following:
{
[self setTranslatesAutoresizingMaskIntoConstraints:YES];
[self addSubview:someView];
[self addSubview:someOtherView];
[self addConstraint...
Is there a read-only generic dictionary available in .NET?
...lt;TKey, TValue>
{
private readonly IDictionary<TKey, TValue> _dictionary;
public ReadOnlyDictionary()
{
_dictionary = new Dictionary<TKey, TValue>();
}
public ReadOnlyDictionary(IDictionary<TKey, TValue> dictionary)
{
_dictionary = dict...
How to merge lists into a list of tuples?
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In Python 2:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> zip(list_a, list_b)
[(1, 5), (2, 6), (3, 7), (4, 8)]
In Python 3:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> list(zi...
How do I break a string over multiple lines?
...se "..." if you need to split lines in the middle of words or want to literally type linebreaks as \n:
key: "Antidisestab\
lishmentarianism.\n\nGet on it."
YAML is crazy.
Block scalar styles (>, |)
These allow characters such as \ and " without escaping, and add a new line (\n) to the end o...
Getting the class name from a static method in Java
...tatic context to mean the current Class in Java, that that "class.xxx" was allowed in either instance or static code to mean this class! The problem with this is that MyClass is verbose and redundant, in the context. But then as much as I like Java it does seem to lean towards verbosity.
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