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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...
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.
...
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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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
...
mailto link with HTML body
... tab is ctrl-i which is %09. Take a look at an ASCII chart like this [asciitable.com/index/asciifull.gif]. The control characters are from 1 through 31. @wide_eyed_pupil
– Jim Bergman
Dec 7 '12 at 6:16
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Declaring a default constraint when creating a table
I am creating a new table in Microsoft SQL server 2000 by writing the code instead of using the GUI, I am trying to learn how to do it "the manual way".
...
Import CSV file into SQL Server
...ll be
inserted with double quotes into rows.
after inserting the data into table you could replace those double quotes with ''.
update table
set columnhavingdoublequotes = replace(columnhavingdoublequotes,'"','')
3) How do we track if some rows have bad data, which import skips?
(does import...
Difference between attr_accessor and attr_accessible
...hat when you create somehow a link between a (Rails) model with a database table, you NEVER, NEVER, NEVER need attr_accessor in your model to create setters and getters in order to be able to modify your table's records.
This is because your model inherits all methods from the ActiveRecord::Base Cl...
How do I efficiently iterate over each entry in a Java Map?
...r();
while (it.hasNext()) {
i += it.next() + it.getValue();
}
Using MutableMap of Eclipse (CS) collections
final long[] i = {0};
mutableMap.forEachKeyValue((key, value) -> {
i[0] += key + value;
});
Perfomance tests (mode = AverageTime, system = Windows 8.1 64-bit, Intel i7-4790 3.6...
How do I remove diacritics (accents) from a string in .NET?
...e limiting yourself to French, you could probably get away with the simple table-based approach in How to remove accents and tilde in a C++ std::string, as recommended by @David Dibben.
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