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mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
Java Reflection: How to get the name of a variable?
...they are in scope.
Perhaps a byte-code engineering library like ASM would allow you to inspect this information at runtime. The only reasonable place I can think of for needing this information is in a development tool, and so byte-code engineering is likely to be useful for other purposes too.
...
MySQL, update multiple tables with one query
...ookID is very important, without it The Books table update would happen to all rows and not only for the row with the specified id. Some lessons are learned the hard way, this one was learned in the terrifing way.
– nheimann1
Mar 24 '15 at 15:06
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SQL Add foreign key to existing column
...sed an error trying to create the relationships to the other table. Thanks all.
– ExceptionLimeCat
Apr 30 '12 at 20:35
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In Python, when should I use a function instead of a method?
...sulation which is so dear to OO design.
The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
Variable interpolation in the shell
I have a variable called filepath=/tmp/name .
3 Answers
3
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Difference between \w and \b regular expression meta characters
...chor like the caret and the dollar sign. It matches at a position that is called a "word boundary". This match is zero-length.
There are three different positions that qualify as word boundaries:
Before the first character in the string, if the first character is
a word character.
After the last ...
How does BLAS get such extreme performance?
...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations.
By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...
An error occurred while validating. HRESULT = '8000000A'
...t item.
We've run into this as well, and had a very unsatisfying support call on this issue with Microsoft. Long story short: it's a known issue, it won't be solved, and Microsoft advises to move away from Visual Studio Setup projects (.vdproj).
We've worked around this issue by triggering the MSI...
Loop through properties in JavaScript object with Lodash
.../lodash.com/docs#forOwn
Note that forOwn checks hasOwnProperty, as you usually need to do when looping over an object's properties. forIn does not do this check.
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