Hi, please ... I need help with following:

I have a table with 11 columns. I would like to create a query where in return I should get values of all columns. Problem is that when I try with 10 elements everything works OK. With 11 I will get compile error.

I found in the Database.SQLite.Simple documentation following:

A collection type that can be converted from a sequence of fields. Instances are provided for tuples up to 10 elements and lists of any length.

So is it possible to select more than 10 columns in one query? It must be right?

working code:

-------------------------

queryX :: Query

queryX = "SELECT el1, el2, el3, el4, el5, el6, el7, el8, el9, el10 FROM tableX" 

saveBtceTickerData :: IO ()

saveBtceTickerData = do

    conn <- open "../mydb.sqlite"

    r <- query_ conn queryX :: IO [(Double, Int, Double, Double, Double, Double, Double, Double, Double, Double)]

    mapM_ print r

    close conn

    putStrLn "done"

non-working code:

-------------------------

someQuery :: Query

someQuery = "SELECT el1, el2, el3, el4, el5, el6, el7, el8, el9, el10, el11 FROM tableX" 

saveBtceTickerData :: IO ()

saveBtceTickerData = do

    conn <- open "../mydb.sqlite"

    r <- query_ conn queryX :: IO [(Double, Int, Double, Double, Double, Double, Double, Double, Double, Double, Double)]

    mapM_ print r

    close conn

    putStrLn "done"

------

Error output:

No instance for (FromRow

                       (Double,

                        Int,

                        Double,

                        Double,

                        Double,

                        Double,

                        Double,

                        Double,

                        Double,

                        Double,

                        Double))

      arising from a use of `query_'

    Possible fix:

      add an instance declaration for

      (FromRow

         (Double,

          Int,

          Double,

          Double,

          Double,

          Double,

          Double,

          Double,

          Double,

          Double,

          Double))

thanks,

m.

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