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Is there a timeout for idle PostgreSQL connections?
...n wait for the message over queue and then perform some more dml operation.Now during that period i.e while it is waiting over queue(for message) as mention above even then the connection with postges is idle. why should i close it.
– Viren
Apr 15 '16 at 18:13
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What is Model in ModelAndView from Spring MVC?
...ll me where i can find what other things the second argument can take like now i understand that it takes variable name , model name , is there any other thing which it can take
– John
Feb 20 '11 at 5:28
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Is there a REAL performance difference between INT and VARCHAR primary keys?
... your database? And pretend that SU never exists? And all references to SU now points to Russia?
– Dainius
Aug 23 '12 at 8:01
6
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Undo git reset --hard with uncommitted files in the staging area
...ache --unreachable $(git for-each-ref --format="%(objectname)") > all
Now the object names of those unreachable commits can be found with:
egrep commit all | cut -d ' ' -f 3
So you can find just the trees and objects that have been added to the index, but not committed at any point, with:
g...
Check if a temporary table exists and delete if it exists before creating a temporary table
...olumn later, it will give an error saying "invalid column". Please let me know what I am doing wrong.
15 Answers
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Can javax.persistence.Query.getResultList() return null?
...t it right?
No matter what, I would code defensively and check for null.
Now the big question: should we treat "null" and an empty List as synonymous? This is where the specs should help us, and don't.
My guess is that a null return (if indeed it could happen) would be equivalent to "I didn't un...
Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
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Update
data.table v1.9.6+ now supports OP's original attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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Is there a job scheduler library for node.js? [closed]
...me function to be ran at certain time (15:30 for example, not x hours from now etc)? If there isn't this kind of library how this should be implemented? Should I just set callback to be called every second and check the time and start jobs scheduled for the time or what?
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How do I set up NSZombieEnabled in Xcode 4?
...orting.
A typical case is when you over-release an object and you don't know which one:
With zombies: -[UITableView release]: message sent to deallocated instance
Without zombies:
This Xcode setting is ignored when you archive the application for App Store submission. You don't need to to...
Professional jQuery based Combobox control? [closed]
... some usability issues with this control, but as a user I don't think I'd know to start typing for the dropdownlist to turn into a textbox.
I much prefer the Combo Dropdown Box, but it still has some features that I'd want and it's still in alpha. The only think I don't like about this other than i...