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Optimistic vs. Pessimistic locking
...stay unmodified for the duration, it's as accurate as pessimistic locking (select for update style) on those same records. The main difference is that optimistic locking incurs overhead only if there's a conflict, whereas pessimistic locking has reduced overhead on conflict. So optimistic is best ...
Is floating point math broken?
...e last place. The table of reciprocals of Y (1/Y) is known as the quotient selection table (QST) in the slow division, and the size in bits of the quotient selection table is usually the width of the radix, or a number of bits of the quotient computed in each iteration, plus a few guard bits. For t...
Surrogate vs. natural/business keys [closed]
...ot more tables into your query than should really be necessary. Compare:
select sum(t.hours)
from timesheets t
where t.dept_code = 'HR'
and t.status = 'VALID'
and t.project_code = 'MYPROJECT'
and t.task = 'BUILD';
against:
select sum(t.hours)
from timesheets t
join departents d on d.dept_i...
How to include a child object's child object in Entity Framework 5
...) method which takes a lambda expression instead of a string. You can then Select() over children with Linq expressions rather than string paths.
return DatabaseContext.Applications
.Include(a => a.Children.Select(c => c.ChildRelationshipType));
...
Doctrine - How to print out the real sql, not just the prepared statement?
...hoWriteSQLWithoutParamsLogger implements SQLLogger
{
const QUERY_TYPE_SELECT="SELECT";
const QUERY_TYPE_UPDATE="UPDATE";
const QUERY_TYPE_INSERT="INSERT";
const QUERY_TYPE_DELETE="DELETE";
const QUERY_TYPE_CREATE="CREATE";
const QUERY_TYPE_ALTER="ALTER";
private $dbPlat...
How to view the list of compile errors in IntelliJ?
... Apparently this "problems" toolbar is only available if you select the "auto compile" mode. see here: jetbrains.com/help/idea/2016.2/problems-tool-window.html
– atom88
Nov 18 '16 at 21:17
...
Is it possible to dynamically compile and execute C# code fragments?
...,100)
where i % 2 == 0
select i;
}
}");
results.Errors.Cast<CompilerError>().ToList().ForEach(error => Console.WriteLine(error.ErrorText));
}
}
The class of primary importance here is the CSharpCodeP...
How do I access my SSH public key?
...="xclip -sel clip" and then pbcopy < ~/.ssh/id_rsa.pub OR simply xclip -selection clipboard < ~/.ssh/id_rsa.pub
– gebbissimo
Mar 8 '19 at 12:29
...
jQuery access input hidden value
...
There's a jQuery selector for that:
// Get all form fields that are hidden
var hidden_fields = $( this ).find( 'input:hidden' );
// Filter those which have a specific type
hidden_fields.attr( 'text' );
Will give you all hidden input field...
PHP: merge two arrays while keeping keys instead of reindexing?
...xing by + operator. This will be very help full in laravel and codeigniter select dropdown.
$empty_option = array(
''=>'Select Option'
);
$option_list = array(
1=>'Red',
2=>'White',
3=>'Green',
);
$arr_option = $empty_...