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Why does ReSharper tell me “implicitly captured closure”?
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For Linq to Sql queries, you may get this warning. The lambda's scope may outlive the method due to the fact that the query is often actualized after the method is out of scope. Depending on your situation, you may want to actualize the ...
Why were pandas merges in python faster than data.table merges in R in 2012?
...ta.table is literally just the sort order (similar to a clustered index in SQL; i.e., that's how the data is ordered in RAM). On the list is to add secondary keys, for example.
In summary, the glaring speed difference highlighted by this particular two-character-column test with over 10,000 unique ...
Is there a MySQL option/feature to track history of changes to records?
I've been asked if I can keep track of the changes to the records in a MySQL database. So when a field has been changed, the old vs new is available and the date this took place. Is there a feature or common technique to do this?
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How do I get current date/time on the Windows command line in a suitable format for usage in a file/
... Is it possible to load files with created date using xp_cmdshell in SQL Server ? I have tried "forfiles" command but to no avail. I have asked a question on stackoverflow, please kindly see the link @ stackoverflow.com/q/32293517/3327081
– kolunar
Sep 2 ...
Node.js vs .Net performance
...ation
nodejs: 228,887
aspnet-stripped: 105,272
Single Query
nodejs-mysql: 88,597
aspnet-stripped-raw: 47,066
Multiple Queries
nodejs-mysql: 8,878
aspnet-stripped-raw: 3,915
Plain Text
nodejs: 289,578
aspnet-stripped: 109,136
In all cases, Node.js tends to be 2x+ faster than IIS.
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How to import multiple .csv files at once?
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+1 seems like producing a single data frame -- the SQL UNION of all CSV files -- is the easiest to work with. Since OP didn't specify whether they want 1 data frame or many data frames, I assumed 1 data frame is best, so I am surprised the accepted answer does not do any of t...
Django dynamic model fields
..._contains='Y') | Q(eav__fever=no)
Hstore, JSON or JSONB fields in PostgreSQL
PostgreSQL supports several more complex data types. Most are supported via third-party packages, but in recent years Django has adopted them into django.contrib.postgres.fields.
HStoreField:
Django-hstore was origina...
How do I migrate a model out of one django app and into a new one?
... you want to move your app you can either rename the database table via an SQL ALTER TABLE statement, or - even simpler - just use the db_table parameter in your model's Meta class to refer to the old name.
If you've used ContentTypes or generic relations anywhere in your code so far, you will prob...
What is a magic number, and why is it bad? [closed]
... the spec.
Now, what you do is you have the 50 in different places - your SQL script (SELECT TOP 50 * FROM orders), your Website (Your Last 50 Orders), your order login (for (i = 0; i < 50; i++)) and possibly many other places.
Now, what happens when someone decides to change 50 to 25? or 75? o...
Difference between initLoader and restartLoader in LoaderManager
...y to run has changed (not the underlying data but the actual query like in SQL statement for a CursorLoader), in which case we will call restartLoader.
The Activity/Fragment life cycle has nothing to do with the decision to use one or the other method (and there's no need to keep track of the calls...