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How does Google's Page Speed lossless image compression work?
...bilities to the fullest, e.g. PNG8+a instead of PNG24+a, optimized Huffman tables in JPEG, etc.
Photoshop doesn't really try hard to do that when saving images for the web, so it's not surprising that any tool beats it.
See
ImageOptim (lossless) and
ImageAlpha (lossy) for smaller PNG files (hi...
django syncdb and an updated model
...ngo currently does not do this automatically. Your options are:
Drop the table from the database, then recreate it in new form using syncdb.
Print out SQL for the database using python manage.py sql (appname), find the added line for the field and add it manually using alter table SQL command. (Th...
What's the difference between VARCHAR and CHAR?
...: when Anon. says "your content is a fixed size" it means the rows of your table must contain all fixed size fields. You get no performance improvement if you use CHAR against VARCHAR in one field, but the table contains other fields that are VARCHAR.
– Marco Demaio
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How to read a .xlsx file using the pandas Library in iPython?
... file using the Pandas Library of python and port the data to a postgreSQL table.
6 Answers
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Fast permutation -> number -> permutation mapping algorithms
... brought down to n*log(n), see section 10.1.1
("The Lehmer code (inversion table)", p.232ff) of the fxtbook:
http://www.jjj.de/fxt/#fxtbook
skip to section 10.1.1.1 ("Computation with large arrays" p.235) for the fast method.
The (GPLed, C++) code is on the same web page.
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How to return only the Date from a SQL Server DateTime datatype
...PU time taken to perform all the pieces. If both queries are run against a table with millions of rows, the CPU time using DateDiff can be close to 1/3rd of the Convert CPU time!
To see execution plans for queries:
set showplan_text on
GO
Both DATEADD and DATEDIFF will execute a CONVERT_IMPLICI...
iPhone Keyboard Covers UITextField
...is is best the explanation out there about this topic. Other tutorials use Table Views, Scroll Views, etc. This actually works without getting into any other complexities, plain and simple. Thanks for sharing this source.
– Renexandro
Feb 17 '14 at 19:39
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Reset the database (purge all), then seed a database
Is there a rake command to wipe out the data in the database tables?
6 Answers
6
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Are there any disadvantages to always using nvarchar(MAX)?
..., the value gets pushed out of row based on may more factors, including sp_tableoptions: msdn.microsoft.com/en-us/library/ms173530.aspx. VARCHAR(255) types can also b pushed out of row, the 'overhead' mentioned may be exactly the same for MAX and 255. It compares MAX types with TEXT types, when they...
What is the purpose of Order By 1 in SQL select statement?
...relation names are allowed in the OREDER BY clause because, in theory, the table correlation names are out of scope i.e. should be ORDER BY PAYMENT_DATE;. Of course, not all SQL implementations conform to Standards.
– onedaywhen
Aug 10 '10 at 7:17
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