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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
...
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...
Can I combine :nth-child() or :nth-of-type() with an arbitrary selector?
Is there a way to select every nth child that matches (or does not match) an arbitrary selector ? For example, I want to select every odd table row, but within a subset of the rows:
...
How to migrate/convert from SVN to Mercurial (hg) on windows
...made
much simpler: Start the TortoiseHG
Workbench from the Start menu. Select
File --> Settings. Select Extensions
from the list. Check the 'convert'
checkbox and click OK. That's it! No
need to try to generate the config
file anymore and search it in the file
system. – bgever M...
Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
How do I do multiple CASE WHEN conditions using SQL Server 2008?
...
Just use this one, You have to use more when they are classes.
SELECT Url='',
p.ArtNo,
p.[Description],
p.Specification,
CASE
WHEN 1 = 1 or 1 = 1
THEN 1
WHEN 2 = 2
THEN 2
WHEN 3 = 3
...
Visual Studio hot keys change occasionally, specifically F6 vs Ctrl-Shift-B for building. WHY?
...
This is because you might have selected "General Development Settings" as your default environment settings for your Visual Studio (which usually we do on the first launch of VS after installing it as it pops up a dialogue box to choose default environment...
Select all DIV text with single mouse click
How to highlight/select the contents of a DIV tag when the user clicks on the DIV...the idea is that all of the text is highlighted/selected so the user doesn't need to manually highlight the text with the mouse and potentially miss a bit of the text?
...
Is there any performance gain in indexing a boolean field?
...
It depends on the actual queries and the selectivity of the index/query combination.
Case A: condition WHERE isok = 1 and nothing else there:
SELECT *
FROM tableX
WHERE isok = 1
If the index is selective enough (say you have 1M rows and only 1k have isok = 1), ...
What is the use of GO in SQL Server Management Studio & Transact SQL?
...
gbn make it SELECT and look at what happens :-)
– SQLMenace
Feb 19 '10 at 21:09
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