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How do I delete a fixed number of rows with sorting in PostgreSQL?
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You could try using the ctid:
DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the row version very quickly,...
LINQ - Left Join, Group By, and Count
...into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.ParentId into grouped
select new { ParentId = grouped.Key, Count = grouped.Count(t=>t.ChildId != null) }
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Heroku Postgres - terminate hung query (idle in transaction)
...'s not desirable or not an option ...)
Find the PID by running this sql:
SELECT pid , query, * from pg_stat_activity
WHERE state != 'idle' ORDER BY xact_start;
(The query may need mending dependent of the version of postgres - eventually, just select * from pg_stat_activity). You'll find the ...
Select DISTINCT individual columns in django?
I'm curious if there's any way to do a query in Django that's not a " SELECT * FROM... " underneath. I'm trying to do a " SELECT DISTINCT columnName FROM ... " instead.
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Xcode + remove all breakpoints
...l breakpoints.
In Xcode4 press CMD(⌘)+6, in Xcode3 press CMD(⌘)+ALT+B.
Select all breakpoints with CMD(⌘)+A and delete them, like deleting text, with backspace.
There's no step 3 :)
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Multiple “order by” in LINQ
...ow in _db.Movies
orderby row.Category, row.Name
select row;
[EDIT to address comment] To control the sort order, use the keywords ascending (which is the default and therefore not particularly useful) or descending, like so:
var movies = from row in _db.Movies
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Eclipse: How do i refresh an entire workspace? F5 doesn't do it
...le->Refresh , it doesn't really refresh anything (perhaps the currently selected project). How do I get eclipse to refresh all of the projects?
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Convert Linq Query Result to Dictionary
... @pawan - that doesn't look right. I'd expect var servers = list.Select( s => new { s.ProjectName, Url = "tcp://" + s.BuildMachineName + ":" + s.PortNumber + "/CruiseManager.rem" } ).ToDictionary( s => s.ProjectName, s.Url ); This creates a dictionary keyed by project name of projec...
LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method ca
... where p.Serial == strItem
select p;
The problem arises because ToString() isn't really executed, it is turned into a MethodGroup and then parsed and translated to SQL. Since there is no ToString() equivalent, the expression fails.
Note:
Make sure ...
Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
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If the field is already a string, this will work
SELECT RIGHT('000'+ISNULL(field,''),3)
If you want nulls to show as '000'
It might be an integer -- then you would want
SELECT RIGHT('000'+CAST(field AS VARCHAR(3)),3)
As required by the question this answer only w...