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Check if a Postgres JSON array contains a string
...te: Here's a demonstration of the performance improvements on a table of 1,000,000 rabbits where each rabbit likes two foods and 10% of them like carrots:
d=# -- Postgres 9.3 solution
d=# explain analyze select info->>'name' from rabbits where exists (
d(# select 1 from json_array_elements(in...
How can you check which options vim was compiled with?
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100
You can see everything vim was compiled with by executing
:version
To query for an exact fea...
Rails new vs create
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answered Mar 18 '10 at 18:46
Steve WeetSteve Weet
26.4k1010 gold badges6161 silver badges8484 bronze badges
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Difference between std::result_of and decltype
I have some trouble understanding the need for std::result_of in C++0x. If I understood correctly, result_of is used to obtain the resulting type of invoking a function object with certain types of parameters. For example:
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Android: how to make keyboard enter button say “Search” and handle its click?
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answered Jul 8 '10 at 15:44
Robby PondRobby Pond
69.2k1515 gold badges119119 silver badges114114 bronze badges
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DBMS_OUTPUT.PUT_LINE not printing
...unlimited]. So you'd do something like
SQL> set serveroutput on size 30000;
SQL> exec print_actor_quotes( <<some value>> );
In SQL Developer, you'd go to View | DBMS Output to enable the DBMS Output window, then push the green plus icon to enable DBMS Output for a particular se...
Can I get a list of files marked --assume-unchanged?
...|
edited Jun 24 '14 at 21:09
Patrick M
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answered ...
How do I find which transaction is causing a “Waiting for table metadata lock” state?
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150
SHOW ENGINE INNODB STATUS \G
Look for the Section -
TRANSACTIONS
We can use INFORMATION_SC...
Which is generally best to use — StringComparison.OrdinalIgnoreCase or StringComparison.InvariantCul
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180
Newer .Net Docs now has a table to help you decide which is best to use in your situation.
From...
What happens if you call erase() on a map element while iterating from begin to end?
... port_map.erase(pm_it);
}
else
{
++pm_it;
}
}
C++03
Erasing elements in a map does not invalidate any iterators.
(apart from iterators on the element that was deleted)
Actually inserting or deleting does not invalidate any of the iterators:
Also see this answer:
Mark Ran...