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SQLite Concurrent Access
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If most of those concurrent accesses are reads (e.g. SELECT), SQLite can handle them very well. But if you start writing concurrently, lock contention could become an issue. A lot would then depend on how fast your filesystem is, since the SQLite engine itself is extremely fast...
Sending a notification from a service in Android
...like this:
// prepare intent which is triggered if the
// notification is selected
Intent intent = new Intent(this, NotificationReceiver.class);
PendingIntent pIntent = PendingIntent.getActivity(this, 0, intent, 0);
// build notification
// the addAction re-use the same intent to keep the example...
Nullable Foreign Key bad practice?
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Using NULL would be a good way to clean up incomplete orders:
SELECT * FROM `orders`
WHERE `started_time` < (UNIX_TIMESTAMP() + 900) AND `customer_id` IS NULL
The above would show orders older than 15 minutes without a related customer ID.
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When/Why to use Cascading in SQL Server?
...alking about to restrict all data accesses to SPs, or at the least all but Select. See my answer under stackoverflow.com/questions/1171769/…
– Cruachan
May 29 '10 at 9:32
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Why should weights of Neural Networks be initialized to random numbers? [closed]
...imization algorithms such as stochastic gradient descent use randomness in selecting a starting point for the search and in the progression of the search.
The progression of the search or learning of a neural network is known as convergence. Discovering a sub-optimal solution or local optima result ...
What's the best manner of implementing a social activity stream? [closed]
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Smallish in this case is such that "select * from events where event.is visible for this user" returns a result in less than a second or two- figure a few hundred thousand rows worth of events.
– Tim Howland
May 26 '09 at ...
Google Gson - deserialize list object? (generic type)
... generics? T[] yourClassList = gson.fromJson(message, T[].class); //cannot select from type variable
– Pawel Cioch
Feb 21 '15 at 17:31
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How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?
...ysqldump fare with large databases in terms of performance? Any way to use SELECT INTO OUTFILE and LOAD DATA smoothly in your suggested process? (Since they generally perform faster)
– Ifedi Okonkwo
Jul 12 '16 at 19:35
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Create table in SQLite only if it doesn't exist already
...bles with the name
tablename = 'KABOOM'
cursor.execute("SELECT count(name) FROM sqlite_master WHERE type='table' AND name=? ", (tablename, ))
print(cursor.fetchone()) # this SHOULD BE in a tuple containing count(name) integer.
# check if the db has existing table...
How do I drop table variables in SQL-Server? Should I even do this?
...4'
SET @SQL = 'DROP TABLE dbo.' + QUOTENAME(@tablename) + '';
IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(@tablename) AND type in (N'U'))
EXEC sp_executesql @SQL;
Works fine on SQL Server 2014
Christophe
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