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PostgreSQL - fetch the row which has the Max value for a column
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There is a new option in Postgressql 9.5 called DISTINCT ON
SELECT DISTINCT ON (location) location, time, report
FROM weather_reports
ORDER BY location, time DESC;
It eliminates duplicate rows an leaves only the first row as ...
Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?
...nt64 value, int decimalPlaces = 1)
{
if (decimalPlaces < 0) { throw new ArgumentOutOfRangeException("decimalPlaces"); }
if (value < 0) { return "-" + SizeSuffix(-value); }
if (value == 0) { return string.Format("{0:n" + decimalPlaces + "} bytes", 0); }
// mag is 0 for bytes, ...
How can I clear event subscriptions in C#?
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edited Jun 29 at 5:51
AustinWBryan
2,86133 gold badges1616 silver badges3535 bronze badges
answer...
Scala best way of turning a Collection into a Map-by-key?
...a.collection.mutable.MapBuilder etc, it seems to me that for each tuple, a new immutable map is created to which the tuple is added.
– jcsahnwaldt Reinstate Monica
Mar 3 '12 at 2:17
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What is the purpose of Order By 1 in SQL select statement?
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answered Aug 10 '10 at 10:51
daven11daven11
2,67622 gold badges2121 silver badges4040 bronze badges
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Error when changing to master branch: my local changes would be overwritten by checkout
...n one branch should stay on that branch until I checkout it again. Hint to newcomers who think that way too: use git stash :)
– Jacek Dziurdzikowski
Nov 22 '18 at 23:03
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Checking if a variable is not nil and not zero in ruby
... I find this perfectly readable, and I would prefer it over a new class. Well done.
– colincr
Jan 16 '18 at 15:23
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“Large data” work flows using pandas
...nch of rows and specific columns, then do an operation (in-memory), create new columns, save these.
(Giving a toy example could enable us to offer more specific recommendations.)
After that processing, then what do you do? Is step 2 ad hoc, or repeatable?
Input flat files: how many, rough total size...
Why are Oracle table/column/index names limited to 30 characters?
...ort this by allowing 30 characters is a bit cheeky. You don't support the new standard, you still support the old standard (albeit 25% of the way to the new standard) Did that make sense?!!?
– cagcowboy
Sep 4 '09 at 10:37
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There is already an open DataReader associated with this Command which must be closed first
...m account in context.Accounts
from guranteer in account.Gurantors
select new AccountsReport
{
CreditRegistryId = account.CreditRegistryId,
AccountNumber = account.AccountNo,
DateOpened = account.DateOpened,
};
return accounts.AsEnumerable()
.Select((account, index) =&g...