Like parameters must be of string value!

  • Thread starter Thread starter Andy B.
  • Start date Start date
A

Andy B.

I ran across this entity framework error: 'Like parameters must be of string
value.' Here is the line of code it mentioned:

Return DBContext.NewsArticles.Where("year(it.CreationDate) like @Year and
it.Archived = true", New ObjectParameter("Year",
Year)).OrderBy("it.CreationDate desc")



The Year parameter is a string since the function parameter was a string and
it got the value from a DropDownList.SelectedItem.Value which is also a
string. What is my problem and how would I fix it?
 
Hi,

Im not sure if the problem is this, but as i know 'and' has higher
precedence than 'like'. (at least in SQL)
-Zsolt
 
Didn't work. I think and has no priority since it is basically sql version
of addition or string addition. Any other ideas?
 
That's correct. Year(date) is an integer. If your comparison needs to be in
SQL Server syntax, you should use the integer comparison for the year and a
numeric comparison for Archived, which I assume is boolean:
Where("year(it.CreationDate) = Cast(@Year as int) and it.Archived <> 0")

If the comparison is being done in your code, then replace the Cast() with a
suitable function.
 
Is there any way to fix this withought having to go all the way through sql
server to create a stored procedure just to do a simple search? I need to
return all records if the % is given as a value (last I knew this was an sql
server wildcard). Otherwise I just need to return the results based on the
year number.
 
I tried just about everything for this part of the where statement:
Cast(year(CreationDate) as string) like @Year

I keep getting errors like int, string, Date, DateTime, varchar and whatever
else datatype you can conjure up isn't valid in the current schema. I am
stuck because entity framework appears to require both sides of a like
statement to be string. This poses a problem because I am sending years to
the query and one of the values to the years is a %. I have to be able to
return all of the years if % is choosen as well as returning based on the
year itself.
 
Andy B. laid this down on his screen :
Is there any way to fix this withought having to go all the way through sql
server to create a stored procedure just to do a simple search? I need to
return all records if the % is given as a value (last I knew this was an sql
server wildcard). Otherwise I just need to return the results based on the
year number.
Click to expand...

% is a wildcard for SQL, but only for string searches (with LIKE), not
for integer values (where LIKE is not supported).

If you have either a % or a year, you might be able to use something
like:

@year = '%' OR Year(theDate) = convert(int, @year)


Hans Kesting
 
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