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mongoDB/mongoose: unique if not null
...ngoDB v1.8+ you can get the desired behavior of ensuring unique values but allowing multiple docs without the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true, unique: true, sparse: true}
Or in the shell:
db.users.ensureIn...
How to check if an object is a certain type
...ou can simply compare them using the Is operator.
So your code should actually be written like this:
Sub FillCategories(ByVal Obj As Object)
Dim cmd As New SqlCommand("sp_Resources_Categories", Conn)
cmd.CommandType = CommandType.StoredProcedure
Obj.DataSource = cmd.ExecuteReader
I...
Ignore python multiple return value
...add gettext functionality to someone else's code (that defines a function called '_') so it should be banned
– nosklo
Jan 11 '09 at 13:32
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How To: Execute command line in C#, get STD OUT results
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edited May 11 '12 at 18:23
user1228
answered Oct 15 '08 at 20:36
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Which parallel sorting algorithm has the best average case performance?
...If we have O(n) processors we would hope for a linear speedup. O(log n) parallel algorithms exist but they have a very high constant. They also aren't applicable on commodity hardware which doesn't have anywhere near O(n) processors. With p processors, reasonable algorithms should take O(n/p log n) ...
Reverse colormap in matplotlib
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The standard colormaps also all have reversed versions. They have the same names with _r tacked on to the end. (Documentation here.)
share
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improve th...
SPAN vs DIV (inline-block)
...turn and have default margin.
Note that inline-block is not supported in all browsers. For instance in Firefox 2 and less you must use:
display: -moz-inline-stack;
which displays slightly different than an inline block element in FF3.
There is a great article here on creating cross browser inl...
Formatting a float to 2 decimal places
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Just in case you're unsure (I was), all of these ways for formatting a float value do provide rounding.
– RenniePet
Nov 12 '17 at 15:03
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Visual Studio Clicking Find Results Opens Code in Wrong Window
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Thanks. Works in VS2015 also
– RandallTo
Nov 24 '15 at 17:29
This solution usually fixes it for me q...
How do I get a PHP class constructor to call its parent's parent's constructor?
I need to have a class constructor in PHP call its parent's parent's (grandparent?) constructor without calling the parent constructor.
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