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How to get the number of days of difference between two dates on mysql?
...lues are
used in the calculation
In your case, you'd use :
mysql> select datediff('2010-04-15', '2010-04-12');
+--------------------------------------+
| datediff('2010-04-15', '2010-04-12') |
+--------------------------------------+
| 3 |
+--------------...
System.Net.Http: missing from namespace? (using .net 4.5)
... Add Reference dialog right-click on your project in Solution Explorer and select Add Reference.... It should look something like:
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How do you count the number of occurrences of a certain substring in a SQL varchar?
...mparing the lengths
Declare @string varchar(1000)
Set @string = 'a,b,c,d'
select len(@string) - len(replace(@string, ',', ''))
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How to increment a pointer address and pointer's value?
...*p)++ => 5
*(p)++ => 5
*++p => 0
*(++p) => 0
I cast the pointer addresses to ints so they could be easily compared.
I compiled it with GCC.
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SQL SELECT speed int vs varchar
...k: A=261MB B=292MB C=322MB
Non-indexed by id: select count(*), select by id: 450ms same on all tables
Insert* one row per TX: B=9ms/record C=9ms/record
Bulk insert* in single TX: B=140usec/record C=180usec/record
Indexed by id, select by id: B=about 2...
How to add directory to classpath in an application run profile in IntelliJ IDEA?
...e F12)
click on the dependencies tab
Click the "+" button on the right and select "Jars or directories..."
Find your path and click OK
In the dialog with "Choose Categories of Selected File", choose Classes (even if it's properties), press OK and OK again
You can now run your application and it will...
What does it mean when a CSS rule is grayed out in Chrome's element inspector?
... because one or more rules from the set are being applied to the currently selected DOM node.
I guess, for the sake of completeness, dev tools shows all the rules from that set, whether they are applied or not.
In the case where a rule is applied to the currently selected element due to inheritance...
Browse the files created on a device by the iOS application I'm developing, on workstation?
...in the bottom half of the window.
In Xcode 6, go to Window -> Devices, select the device, select the app name under Installed Apps, click the settings gearbox, then select Download container.... In finder, double finger tap the package and select Show package contents.
...
How to get the top 10 values in postgresql?
...
For this you can use limit
select *
from scores
order by score desc
limit 10
If performance is important (when is it not ;-) look for an index on score.
Starting with version 8.4, you can also use the standard (SQL:2008) fetch first
select *
from...
Fetch the row which has the Max value for a column
... multiple rows for the userid where the maximum date is on multiple rows.
select userid,
my_date,
...
from
(
select userid,
my_date,
...
max(my_date) over (partition by userid) max_my_date
from users
)
where my_date = max_my_date
"Analytic functions rock"
Edi...