CODEWITHSUNDEEP
delphit-sqldbexpress
Marks
Marks

Reputation: 3663

TSQLQuery - Cursor not returned from query

Right now, I am trying to get rid of some old searching code in a delphi programm, and I want to push the searching to the sql-server the program is using. For this I created this query, which is very similar to a query I use in a different C# program.

The query works just fine using the SQL Management Studio or from a C# program, but with Delphi I get a "Cursor not returned from query" error.

This is the query

DECLARE @SearchString NVARCHAR(MAX);
SET @SearchString = ':Param1';
IF @SearchString = '' SET @SearchString = '%';

--Table for splitted values
DECLARE @SearchItms TABLE
(
Item NVARCHAR(MAX)
)

--Split Operator
DECLARE @SplitOn NVARCHAR(MAX)
SET @SplitOn = ' '; --Split Keywords on space

--Splitting
While (Charindex(@SplitOn,@SearchString)>0)
Begin
    Insert Into @SearchItms (Item)
    Select ('%' + Substring(@SearchString,1,Charindex(@SplitOn,@SearchString)-1) + '%')

    Set @SearchString = Substring(@SearchString,Charindex(@SplitOn,@SearchString)+1,len(@SearchString))
End

--Add last Item
Insert Into @SearchItms (Item) 
Select ('%' + @SearchString + '%')

--Select fitting items
SELECT MyTable.*
FROM MyTable INNER JOIN SecondTable ON (MyTable.Key = SecondTable.Key)
WHERE
NOT EXISTS(
  SELECT * FROM @SearchItms WHERE NOT(
     (OneField IS NOT NULL AND OneField LIKE Item)
  OR (OneDateField IS NOT NULL AND (convert(varchar, OneDateField, 104) LIKE Item) OR (convert(varchar, OneDateField, 114) LIKE Item ) )
  OR (AnotherField IS NOT NULL AND AnotherField LIKE Item)
  OR (LastField IS NOT NULL AND LastField LIKE Item)
  )
)

One strange thing is, that when I remove

--Add last Item
Insert Into @SearchItms (Item) 
Select ('%' + @SearchString + '%')

I don't get the "Cursor not returned from query" error. But with a search string, where I get only 10 Results in the SQL Management Studio, I get all items in the database in Delphi, like the search did not do anything.

This happens also in a simple test program where I just have a Form, a TSQLConnection, TSQLQuery, TDataSetProvider and a ClientDataSet.

Can someone tell me whats the problem here? Since the query works fine in other environments, I think it should be OK.

Many thanks for any help.

Upvotes: 4

Views: 4864

Answers (2)

Marks
Marks

Reputation: 3663

As ldsandon mentioned in his post, the problem seems to be, that its not a simple Query, but a complete script. But since non of the other dbExpress units seems to be able to handle this I found a way to make it working.

Just add a SET NOCOUNT ON; to the beginning of the script, and close the script with SET NOCOUNT OFF;

I think this surpresses the 'xx rows effected' message from the inserts and therefore makes it possible to run without errors.

If you know a better way to run the script without errors, let me know.

Thanks.

Upvotes: 5

user160694
user160694

Reputation:

This is not a query - this is a script. Usually a Delphi TQuery component can handle a single SQL statement, not multiple ones (you have INSERTs first and then a SELECT). It may be the INSERT that obviously does not return a cursor. You can try to use a TSQLDataset and see if it can handle such a kind of SQL Server "anonymous block", or turn it into a stored procedure and call it from your Delphi program.

Upvotes: 2

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