Step by Step solution about How to resolve the algorithm Parameterized SQL statement step by step in the Haskell programming language

The source code you provided shows a typical update function that is used in a Haskell program to update data in a relational database. It takes the following arguments:

• conn: An IConnection object, which represents a connection to the database.
• name: A String representing the name of the player to update.
• score: An Int representing the new score for the player.
• active: A Bool representing whether the player is active or not.
• jerseyNum: An Int representing the jersey number of the player.

The function first executes an SQL UPDATE statement on the players table, using the run function from the Database.HDBC library. The SQL statement is written as a multiline string, and the toSql function is used to convert the Haskell values to SQL values.

After the SQL statement has been executed, the commit function is called to commit the changes to the database. Finally, the function returns a Bool value indicating whether the update was successful, which is determined by checking if the number of rows affected by the update is equal to 1.

The main function in this source code is simply a placeholder, and it is not defined. This is common in Haskell programs, as the main function is typically defined in a separate module.

Overall, this source code shows how to use the Database.HDBC library in Haskell to update data in a relational database.

module Main (main) where

import           Database.HDBC (IConnection, commit, run, toSql)

updatePlayers :: IConnection a => a -> String -> Int -> Bool -> Int -> IO Bool
updatePlayers conn name score active jerseyNum = do
    rowCount <- run conn
        "UPDATE players\
        \ SET name = ?, score = ?, active = ?\
        \ WHERE jerseyNum = ?"
        [ toSql name
        , toSql score
        , toSql active
        , toSql jerseyNum
        ]
    commit conn
    return $ rowCount == 1

main :: IO ()
main = undefined