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Best practices for storing postal addresses in a database (RDBMS)?
...eal letters or parcels by mail. The first_name / last_name are only needed if you want to address the customer directly, e.g. by email ("Dear Mister <last_name>"). Or is there any other purpose/ benefit to it?
– luba
Apr 10 '17 at 16:00
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Can someone explain collection_select to me in clear, simple terms?
...ll be: <select name="post[author_id]">...
# then you should specify some collection or array of rows.
# It can be Author.where(..).order(..) or something like that.
# In your example it is:
Author.all,
# then you should specify methods for generating options
:id, # ...
When to use a View instead of a Table?
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Oh there are many differences you will need to consider
Views for selection:
Views provide abstraction over tables. You can add/remove fields easily in a view without modifying your underlying schema
Views can model complex joins easily.
Vie...
Rails: where does the infamous “current_user” come from?
...his only come from Devise? and do I have to manually define it myself even if I use Devise? Are there prerequisites to using current_user (like the existence of sessions, users, etc)?
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Merging two arrays in .NET
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If you can manipulate one of the arrays, you can resize it before performing the copy:
T[] array1 = getOneArray();
T[] array2 = getAnotherArray();
int array1OriginalLength = array1.Length;
Array.Resize<T>(ref array1, a...
Why historically do people use 255 not 256 for database field magnitudes?
...oose to use a single byte to indicate the length of the data in the field. If the limit were 256 or greater, two bytes would be needed.
A value of length zero is certainly valid for varchar data (unless constrained otherwise). Most systems treat such an empty string as distinct from NULL, but some ...
What is the difference between 127.0.0.1 and localhost
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Well, the most likely difference is that you still have to do an actual lookup of localhost somewhere.
If you use 127.0.0.1, then (intelligent) software will just turn that directly into an IP address and use it. Some implementations of gethostbyn...
Outputting data from unit test in python
If I'm writing unit tests in python (using the unittest module), is it possible to output data from a failed test, so I can examine it to help deduce what caused the error? I am aware of the ability to create a customized message, which can carry some information, but sometimes you might deal with m...
Why does this iterative list-growing code give IndexError: list assignment index out of range?
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for l in i:
j.append(l)
Of course, you'd never do this in practice if all you wanted to do was to copy an existing list. You'd just do:
j = list(i)
Alternatively, if you wanted to use the Python list like an array in other languages, then you could pre-create a list with its elements set ...
How do you remove the title text from the Android ActionBar?
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@domji84, You can specify the theme of each activity in the manifest file.
– ashishduh
Jan 15 '14 at 17:42
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