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Facebook database design?
...O_INCREMENT=2 DEFAULT CHARSET=utf8;
Friends of Friends Query:
(
select friend_id
from friends
where user_id = 1
) union (
select distinct ff.friend_id
from
friends f
join friends ff on ff.user_id = f.friend_id
where f.use...
How can I turn a List of Lists into a List in Java 8?
... .collect(Collectors.toList())
This is would be similar in SQL to having SELECT statements within SELECT statements.
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CSS3 :unchecked pseudo-class
...
:unchecked is not defined in the Selectors or CSS UI level 3 specs, nor has it appeared in level 4 of Selectors.
In fact, the quote from W3C is taken from the Selectors 4 spec. Since Selectors 4 recommends using :not(:checked), it's safe to assume that ther...
Is there a timeout for idle PostgreSQL connections?
...ement an idle connection reaper. Have a cron job run something like this:
SELECT pg_terminate_backend(pid)
FROM pg_stat_activity
WHERE datname = 'regress'
AND pid <> pg_backend_pid()
AND state = 'idle'
AND state_change < current_timestamp - INTERVAL '5' MINUTE;
...
Can't delete virtual device from Eclipse, android
...e inside [Your Device].avd folder
From Android Studio
Open AVD Manager
Select virtual device that you want to delete
Click down arrow at the end and select [Show on Disk] it will open directory
Find *.lock files and delete inside [Your Device].avd folder
After these steps it will allow you to ...
Best way to store time (hh:mm) in a database
...t a glance and performing calculations on them are straightforward.
E.g.
SELECT DATEDIFF(MINUTE, event_start, event_end)
ISO8601 date standard
If using SQLite then you don't have this, so instead use a Text field and store it in ISO8601 format eg.
"2013-01-27T12:30:00+0000"
Notes:
This use...
Are there any side effects of returning from inside a using() statement?
...nCreated descending
where t.Id == singleId
select t).SingleOrDefault();
}
}
Indeed, I might even be tempted to use dot notation, and put the Where condition within the SingleOrDefault:
public static Transaction GetMostRecentTransaction(int singleId)
{
using...
How to handle click event in Button Column in Datagridview?
...ast the sender to type DataGridView, we can get the Columns collection and select the current column using e.ColumnIndex. Then check if that object is of type DataGridViewButtonColumn.
Of course, if you need to distinguish between multiple buttons per grid, you can then select based on the column n...
Is there a good reason to use upper case for SQL keywords? [closed]
...re highlighted, not the entire query. His second example would look like:
SELECT name, id, xtype, uid, info, status,
base_schema_ver, replinfo, parent_obj, crdate,
ftcatid, schema_ver, stats_schema_ver, type,
userstat, sysstat, indexdel, refdate, version,
deltrig, instrig, updtrig, seltrig, cat...
Changing the size of a column referenced by a schema-bound view in SQL Server
...ethod. not just the return on the search process.
view the table class
select * from class
change the length of the columns FacID (seen as "faci") and classnumber (seen as "classnu") to fit the whole labels.
alter table class modify facid varchar (5);
alter table class modify classnumber v...