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Is there any performance gain in indexing a boolean field?
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Not really. You should think about it like a book. If there were only 3 kinds of words in a book and you index all of them, you would have the same number of index pages as normal pages.
There would be a performance gain if there are relatively few records of one value. For...
How to call Base Class's __init__ method from the child class? [duplicate]
If I have a python class as:
4 Answers
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What to add for the update portion in ConcurrentDictionary AddOrUpdate
...dio you can only guess the meaning of the 2 parameters. However in the specific case, that @user438331 asks about, I think the solution in my answer using a simple indexer is better.
– Niklas Peter
Sep 26 '15 at 10:33
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How to replace text between quotes in vi
...nge inside parentheses
dit - delete inside an HTML tag, etc.
More about different vim text objects here.
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How to change webservice url endpoint?
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To add some clarification here, when you create your service, the service class uses the default 'wsdlLocation', which was inserted into it when the class was built from the wsdl. So if you have a service class called SomeService, and you cr...
Checking a Python module version at runtime
...ernative, I'd like to suggest that you don't check at run time (don't know if that's a hard requirement or not). For the python stuff I write that has external dependencies (3rd party libraries), I write a script that users can run to check their python install to see if the appropriate versions of...
Function to return only alpha-numeric characters from string?
...pt a-z, A-Z and 0-9:
$result = preg_replace("/[^a-zA-Z0-9]+/", "", $s);
If your definition of alphanumeric includes letters in foreign languages and obsolete scripts then you will need to use the Unicode character classes.
Try this to leave only A-Z:
$result = preg_replace("/[^A-Z]+/", "", $s);...
How to store decimal values in SQL Server?
...column datatype is decimal(4,2)? When I insert the value, it is getting modified to "4.50"
– Arun
Feb 10 '15 at 7:23
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How to empty/destroy a session in rails?
... available for clearing hash will work with sessions.
session.clear
or
if specific keys have to be destroyed:
session.delete(key)
Tested in rails 3.2
added
People have mentioned by session={} is a bad idea. Regarding session.clear, Lobati comments- It looks like you're probably better off...
'str' object does not support item assignment in Python
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Then if I would to read the characters from the string and copy them some where, then how can I do that?
– Rasmi Ranjan Nayak
May 17 '12 at 7:21
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