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PostgreSQL: Difference between text and varchar (character varying)
...ange the limit in live environment (requires exclusive lock while altering table)
varchar – just like text
text – for me a winner – over (n) data types because it lacks their problems, and over varchar – because it has distinct name
The article does detailed testing to show that the...
How does C compute sin() and other math functions?
...ximations for both sin(x) and cos(x), then using values from a precomputed table to refine the approximation.
When |x| > 2, none of the above algorithms would work, so the code starts by computing some value closer to 0 that can be fed to sin or cos instead.
There's yet another branch to deal wit...
How to vertically align elements in ?
...n, you're not worrying about IE or older browsers.
So you can use display:table-cell and display:table-row like so:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.or...
TSQL - How to use GO inside of a BEGIN .. END block?
...t using SET NOEXEC.
IF not whatever
BEGIN
SET NOEXEC ON;
END
ALTER TABLE dbo.EMPLOYEE ADD COLUMN EMP_IS_ADMIN BIT NOT NULL
GO
UPDATE dbo.EMPLOYEE SET EMP_IS_ADMIN = whatever
SET NOEXEC OFF;
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How to create a HashMap with two keys (Key-Pair, Value)?
...mply use:
Map<Key, V> map = //...
and:
map.get(new Key(2, 5));
Table from Guava
Table<Integer, Integer, V> table = HashBasedTable.create();
//...
table.get(2, 5);
Table uses map of maps underneath.
N dimensions
Notice that special Key class is the only approach that scales to...
Expand div to max width when float:left is set
...
The best way is to use a simple 2 cols table instead of wasting time adding tons of CSS not-cross-browser-compatibles tricks
– Marco Demaio
Nov 23 '12 at 10:22
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How to detect the end of loading of UITableView
I want to change the offset of the table when the load is finished and that offset depends on the number of cells loaded on the table.
...
Why do we not have a virtual constructor in C++?
...uctor ends.In order for the constructor to be dispatched using the virtual table , there has to be an existing object with a pointer to the virtual table , but how can a pointer to the virtual table exist if the object still doesn't exist? :)
Logic reason
You use the virtual keyword when you want ...
Convert Unix timestamp into human readable date using MySQL
...
Use FROM_UNIXTIME():
SELECT
FROM_UNIXTIME(timestamp)
FROM
your_table;
See also: MySQL documentation on FROM_UNIXTIME().
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How do you convert a DataTable into a generic list?
...
If you're using .NET 3.5, you can use DataTableExtensions.AsEnumerable (an extension method) and then if you really need a List<DataRow> instead of just IEnumerable<DataRow> you can call Enumerable.ToList:
IEnumerable<DataRow> sequence = dt.AsEnume...