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In Ruby on Rails, what's the difference between DateTime, Timestamp, Time and Date?
...ave DATE, DATETIME, TIME and TIMESTAMP column data types; just as you have CHAR, VARCHAR, FLOAT and INTEGER.
So, you ask, what's the difference? Well, some of them are self-explanatory. DATE only stores a date, TIME only stores a time of day, while DATETIME stores both.
The difference between DATE...
INSERT INTO … SELECT FROM … ON DUPLICATE KEY UPDATE
...olumns named in the INSERT INTO clause, and the second part references the SELECT columns.
INSERT INTO lee(exp_id, created_by, location, animal, starttime, endtime, entct,
inact, inadur, inadist,
smlct, smldur, smldist,
larct, lardur, lardist,
...
Rails find record with zero has_many records associated [duplicate]
..._joins(:photos).where(photos: {id: nil})
which will result in SQL like:
SELECT cities.*
FROM cities LEFT OUTER JOIN photos ON photos.city_id = city.id
WHERE photos.id IS NULL
Using includes:
City.includes(:photos).where(photos: {id: nil})
will have the same result, but will result in much ug...
MySQL Query GROUP BY day / month / year
... for added clarity in some cases such as where records span several years. SELECT COUNT(event_id), DATE_FORMAT(event_start, '%Y/%m')
– Ric
Apr 4 '13 at 10:25
...
Why is it OK to return a 'vector' from a function?
...oing to return a..." << std::endl;
return a;
}
int main(int argc, char** argv)
{
MyClass b = my_function();
MyClass c;
c = my_function();
return 0;
}
The output is the following:
run my_function()
run constructor MyClass::MyClass()
my_function is going to return a...
run constr...
Any tips on how to organize Eclipse environment on multiple monitors?
...s don't "communicate", e.g. javadoc view in one window won't be updated by selections in the other, similarly jUnit.
– David
Nov 2 '11 at 15:01
...
Node.js throws “btoa is not defined” error
...
The solutions posted here don't work in non-ascii characters (i.e. if you plan to exchange base64 between Node.js and a browser). In order to make it work you have to mark the input text as 'binary'.
Buffer.from('Hélló wórld!!', 'binary').toString('base64')
This gives...
Convert INT to VARCHAR SQL
I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error:
...
Write a number with two decimal places SQL server
...
try this
SELECT CONVERT(DECIMAL(10,2),YOURCOLUMN)
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Eclipse java debugging: source not found
...issing source will continue to show "missing source".
Edit Source Lookup
Select the Edit Source Lookup... command [ Edit Source Lookup ] to open the Source Path Dialog, which allows you to make changes to the source lookup path of the selected debug target.
IMPORTANT Restart Eclipse after t...