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How to get the top 10 values in postgresql?
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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...
Get first day of week in SQL Server
...in that there should be some sensible logic built in to round up or down:
SELECT DATEDIFF(YEAR, '2010-01-01', '2011-12-31');
SELECT DATEDIFF(YEAR, '2010-12-31', '2011-01-01');
To answer how to get a Sunday:
If you want a Sunday, then pick a base date that's not a Monday but rather a Sunday. For ...
Rails raw SQL example
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You can do this:
sql = "Select * from ... your sql query here"
records_array = ActiveRecord::Base.connection.execute(sql)
records_array would then be the result of your sql query in an array which you can iterate through.
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What's the Linq to SQL equivalent to TOP or LIMIT/OFFSET?
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In VB:
from m in MyTable
take 10
select m.Foo
This assumes that MyTable implements IQueryable. You may have to access that through a DataContext or some other provider.
It also assumes that Foo is a column in MyTable that gets mapped to a property name.
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Getting a 404 from WMSvc via MSDeploy.exe
...el > Programs and Features. Right-click "Microsoft Web Deploy 3.5" and select "Change". From the installer select "Change" and "IIS Deployment Handler" was available as an option (was disabled at first. Also "Configure for Non-Administrator Deployments" and "Management Service Delegation UI" w...
select into in mysql
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Use the CREATE TABLE SELECT syntax.
http://dev.mysql.com/doc/refman/5.0/en/create-table-select.html
CREATE TABLE new_tbl SELECT * FROM orig_tbl;
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How does one reorder columns in a data frame?
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You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...
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,
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from
(
select userid,
my_date,
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max(my_date) over (partition by userid) max_my_date
from users
)
where my_date = max_my_date
"Analytic functions rock"
Edi...
Convert Month Number to Month Name Function in SQL
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A little hacky but should work:
SELECT DATENAME(month, DATEADD(month, @mydate-1, CAST('2008-01-01' AS datetime)))
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Group by in LINQ
... p in persons
group p.car by p.PersonId into g
select new { PersonId = g.Key, Cars = g.ToList() };
Or as a non-query expression:
var results = persons.GroupBy(
p => p.PersonId,
p => p.car,
(key, g) => new { PersonId = key, Cars = g.ToList() });
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