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Is using Random and OrderBy a good shuffle algorithm?
...e naive version). Durstenfeld/Knuth achieve O(n) not by assignment, but by selection from a decreasing set and swapping. This way the random number selected may repeat and the algorithm only takes O(n).
– tvanfosson
Aug 17 '09 at 12:18
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Can the :not() pseudo-class have multiple arguments?
I'm trying to select input elements of all type s except radio and checkbox .
5 Answers
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How to delete a certain row from mysql table with same column values?
...ike this:
DELETE FROM your_table WHERE id_users=1 AND id_product=2
LIMIT (SELECT COUNT(*)-1 FROM your_table WHERE id_users=1 AND id_product=2)
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Using varchar(MAX) vs TEXT on SQL Server
...es ('b')
insert into @table values ('c')
insert into @table values ('d')
select *
from @table
where a ='a'
This give an error:
The data types text and varchar are incompatible in the equal to operator.
Wheras this does not:
declare @table table (a varchar(max))
Interestingly, LIKE still wo...
Determine what attributes were changed in Rails after_save callback?
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The "selected" answer didn't work for me. I'm using rails 3.1 with CouchRest::Model (based on Active Model). The _changed? methods don't return true for changed attributes in the after_update hook, only in the before_update hook. ...
When to use UICollectionView instead of UITableView?
...onview, you don't need to set buttons with tags or other things by getting selected items values. You can simply get -(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath and in UITableViewDelegate:
`-(void)tableView:(UITableView *)tableView didS...
Can you use hash navigation without affecting history?
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Unless you use :target selectors ... then history functions are useless, as that part of the spec (css interaction with history ops) seems to be not defined currently, and style does not get recomputed on history replace by most/all browsers.
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Disabling Chrome cache for website development
...ck (or hold left click) on the reload button at the top of the browser and select "Empty Cache and Hard Reload."
This will go beyond "Hard Reload" to empty the cache entirely, ensuring that anything downloaded via javascript or etc. will also avoid using the cache. You don't have to mess with set...
Why does SSL handshake give 'Could not generate DH keypair' exception?
...DHE_.... The later would happen if I added BouncyCastle. If TLS_ECDHE_ was selected, MOST OF the time it worked, but not ALWAYS, so adding even BouncyCastle provider was unreliable (failed with same error, every other time or so). I guess somewhere in the Sun SSL implementation sometimes it choose D...
How to check status of PostgreSQL server Mac OS X
...using psql to run a simple query and checking the exit code, e.g. psql -c 'SELECT 1', or use pg_isready to check the connection status.
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