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Find difference between timestamps in seconds in PostgreSQL
... It will Subtract arguments, producing a "symbolic" result that uses years and months. It wont give the difference in seconds.
– Igor Romanchenko
Dec 24 '12 at 11:55
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TypeError: ObjectId('') is not JSON serializable
...an aggregated function on document using Python, It returns valid response and i can print it but can not return it.
16 Ans...
How to debug external class library projects in visual studio?
...le JMC in order to see it. Otherwise the code will be treated as external and largely hidden from your view.
EDIT
When you're broken in your code try the following.
Debug -> Windows -> Modules
Find the DLL for the project you are interested in
Right Click -> Load Symbols -> Select...
Will docker container auto sync time with the host machine?
...are running Kitematic, which is now the suggested mechanism for getting up and running on Docker in OSX, you will have to periodically run this command:
docker-machine ssh default 'sudo ntpclient -s -h pool.ntp.org'
Or, for older versions of docker
docker-machine ssh dev 'sudo ntpclient -s -h po...
Delete duplicate records in SQL Server?
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You can do this with window functions. It will order the dupes by empId, and delete all but the first one.
delete x from (
select *, rn=row_number() over (partition by EmployeeName order by empId)
from Employee
) x
where rn > 1;
Run it as a select to see what would be deleted:
select *...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...ies, levels=c(levels(iris$Species), "empty_level"))
# Species is a factor and empty groups are included in the output
iris %>% group_by(Species, .drop=FALSE) %>% tally
#> Species n
#> 1 setosa 50
#> 2 versicolor 50
#> 3 virginica 50
#> 4 empty_level ...
Select first 4 rows of a data.frame in R
...row.index, column.index]
Read help(`[`) for more detail on this subject, and also read about index matrices in the Introduction to R.
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Remove blank lines with grep
I tried grep -v '^$' in Linux and that didn't work. This file came from a Windows file system.
14 Answers
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CSS: how to position element in lower right?
...m trying to position the text element "Bet 5 days ago" in the lower right-hand corner. How can I accomplish this? And, more importantly, please explain so I can conquer CSS!
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Remove redundant paths from $PATH variable
...d it to any .bashrc, bash.bashrc, /etc/profile - whatever fits your system and user needs.
Note: This is for Linux. We'll make this clear for new coders. (` , ') Don't try to SET = these.
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