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MongoDB and “joins” [duplicate]
...ll only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are ...
Difference between database and schema
What's the difference between a Database and a Schema in SQL Server? Both are the containers of tables and data.
5 Answers
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WatiN or Selenium? [closed]
... tests of our presentation soon. It seems that everyone recommends WatiN and Selenium . Which do you prefer for automated testing of ASP.NET web forms? Which of these products work better for you?
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How can I find the first occurrence of a sub-string in a python string?
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@Regressor: look into regex and word boundaries.
– mechanical_meat
Apr 12 at 23:29
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Array.Copy vs Buffer.BlockCopy
Array.Copy and Buffer.BlockCopy both do the same thing, but BlockCopy is aimed at fast byte-level primitive array copying, whereas Copy is the general-purpose implementation. My question is - under what circumstances should you use BlockCopy ? Should you use it at any time when you are copyi...
JavaScript data grid for millions of rows [closed]
...s set to the total height of all the rows. The rows are still being added and removed as the user is scrolling, but the scrolling itself is done by the browser. That allows it to be very fast yet smooth (onscroll events are notoriously slow). The caveat is that there are bugs/limits in the browse...
Transaction count after EXECUTE indicates a mismatching number of BEGIN and COMMIT statements. Previ
I have an Insert stored procedure which will feed data to Table1 and get the Column1 value from Table1 and call the second stored procedure which will feed the Table2.
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Why does one hot encoding improve machine learning performance?
...ced that when One Hot encoding is used on a particular data set (a matrix) and used as training data for learning algorithms, it gives significantly better results with respect to prediction accuracy, compared to using the original matrix itself as training data. How does this performance increase h...
How do I list the functions defined in my shell?
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declare -F
Function names and definitions may be listed with the -f option to the
declare builtin command (see Bash Builtins). The -F option to declare
will list the function names only
(and optionally the source file and line number).
Bash Re...
Compare floats in php
...same value do not need to actually be identical. So if $a is a literal .17 and $b arrives there through a calculation it can well be that they are different, albeit both display the same value.
Usually you never compare floating-point values for equality like this, you need to use a smallest accept...