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SQL Server indexes - ascending or descending, what difference does it make?
...ces to rows.
Since the table is clustered, the references to rows are actually the values of the pk. They are also ordered within each value of col1.
This means that that leaves of the index are actually ordered on (col1, pk), and this query:
SELECT col1, pk
FROM mytable
ORDER BY
col1...
UICollectionView reloadData not functioning properly in iOS 7
...nd probing. I feel this is an iOS 7 bug. Forcing the main thread will run all UIKit related messages. I seem to run into this when popping to the view from another view controller. I refresh the data on viewWillAppear. I could see the data and collection view reload call, but the UI was not updat...
How can I add an item to a SelectList in ASP.net MVC
Basically I am looking to insert an item at the beginning of a SelectList with the default value of 0 and the Text Value of " -- Select One --"
...
Passport.js - Error: failed to serialize user into session
...d serializing user information but only id's (for bloat/perf reasons personally).
– electblake
Jan 22 '16 at 20:03
2
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What do “branch”, “tag” and “trunk” mean in Subversion repositories?
...ode in the trunk. If the major changes work according to plan, they are usually merged back into the trunk.
Tag will be a point in time on the trunk or a branch that you wish to preserve. The two main reasons for preservation would be that either this is a major release of the software, whether alp...
What is mattr_accessor in a Rails module?
I couldn't really find this in Rails documentation but it seems like 'mattr_accessor' is the Module corollary for 'attr_accessor' (getter & setter) in a normal Ruby class .
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How can I extract the folder path from file path in Python?
....path.split(os.path.abspath(existGDBPath))
('T:\\Data\\DBDesign', 'DBDesign_93_v141b.mdb')
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How to list the tables in a SQLite database file that was opened with ATTACH?
....schema tablename
Print the entire table:
SELECT * FROM tablename;
List all of the available SQLite prompt commands:
.help
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How to encrypt/decrypt data in php?
...er generator. The following example would be recommended (>= 5.3):
$key_size = 32; // 256 bits
$encryption_key = openssl_random_pseudo_bytes($key_size, $strong);
// $strong will be true if the key is crypto safe
This can be done once or multiple times (if you wish to create a chain of encrypti...
How to export collection to CSV in MongoDB?
How do you export all the records in a MongoDB collection to a .csv file?
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