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MySQL: how to get the difference between two timestamps in seconds
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You could use the TIMEDIFF() and the TIME_TO_SEC() functions as follows:
SELECT TIME_TO_SEC(TIMEDIFF('2010-08-20 12:01:00', '2010-08-20 12:00:00')) diff;
+------+
| diff |
+------+
| 60 |
+------+
1 row in set (0.00 sec)
You could also use the UNIX_TIMESTAMP() function as @Amber suggested in a...
How to write “Html.BeginForm” in Razor
...data" }))
{
@Html.ValidationSummary(true)
<fieldset>
Select a file <input type="file" name="file" />
<input type="submit" value="Upload" />
</fieldset>
}
and generates as expected:
<form action="/Upload/Upload" enctype="multipart/form-data" m...
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
...o training and validation (again, 80/20 is a fair split).
Subsample random selections of your training data, train the classifier with this, and record the performance on the validation set
Try a series of runs with different amounts of training data: randomly sample 20% of it, say, 10 times and obs...
What is DOCTYPE?
...de), depending on the exact spelling of the DOCTYPE. You want to use it to select a browser mode that best suits your page.
Formally, in SGML and XML, a DOCTYPE declaration is a reference to a Document Type Definition (DTD), which specifies the formal syntax rules of the markup language. No browser...
Adding IN clause List to a JPA Query
...need (...):
@NamedQuery(name = "EventLog.viewDatesInclude",
query = "SELECT el FROM EventLog el WHERE el.timeMark >= :dateFrom AND "
+ "el.timeMark <= :dateTo AND "
+ "el.name IN :inclList")
share
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Should I use “hasClass” before “addClass”? [duplicate]
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Hey Jon :) It is mouse selectable as well.. (click on line number and shift+click on another to select all lines..)
– Gabriele Petrioli
Nov 13 '12 at 10:30
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List all files in one directory PHP [duplicate]
...de and reviews used something like foreach(scandir($x) as $file) if ($file selection) {...}, and glob() not need the if, neither regular expressions or array_diffs for selection.
– Peter Krauss
Sep 14 '16 at 1:38
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How do you list all triggers in a MySQL database?
...w triggers;
or you can access the INFORMATION_SCHEMA table directly by:
select trigger_schema, trigger_name, action_statement
from information_schema.triggers
You can do this from version 5.0.10 onwards.
More information about the TRIGGERS table is here.
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Merge multiple lines (two blocks) in Vim
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You can certainly do all this with a single copy/paste (using block-mode selection), but I'm guessing that's not what you want.
If you want to do this with just Ex commands
:5,8del | let l=split(@") | 1,4s/$/\=remove(l,0)/
will transform
work it
make it
do it
makes us
harder
better
faster...
Why is an int in OCaml only 31 bits?
...space and a number of special objects like true, false, nil, the 127 ASCII characters, some commonly used short strings, the empty list, the empty object, the empty array and so on near the 0 address.
For example, in the MRI, YARV and Rubinius Ruby interpreters, integers are encoded the way I descr...