Learning MySQL - N00B :(

[FlyingSpoon]

function registerPlayer(username,password) 
handler = mysql_connect( host, username, password, db ) 
    if not (username == "") then 
        if not (password == "") then 
                    local account = getAccount (username,password) 
                    if (account == false) then 
                        local accountAdded = mysql_query(handler,"INSERT INTO accounts VALUES "(tostring(username),tostring(password))"';") 
                        if (accountAdded) then 
                            outputChatBox ("#FF0000* #00FF00You have sucessfuly registered! [username: #FFFFFF" .. username .. " #00FF00| Password: #FFFFFF" .. password .. "#00FF00 ]",source,255,255,255,true ) 
                            triggerClientEvent(source,"achievement:onRegister", getRootElement()) 
                        else 
                            outputChatBox("An error occured! Please choose a different username/or password!", source, 255, 0, 0) 
                        end 
                    else 
                           outputChatBox("An account with this username already exists!", source, 255, 0, 0) 
                    end 
                else 
                        outputChatBox("Null!", source, 255, 0, 0) 
                end 
            else 
                       outputChatBox("Null!", source, 255, 0, 0) 
            end 
end 
addEvent("onRequestRegister",true) 
addEventHandler("onRequestRegister",getRootElement(),registerPlayer) 

I am really stuck, I dont even know what's going on, please someone help me out! Thanks

[2015-08-12 12:57:49] SCRIPT ERROR: login\s_login.lua:7: ')' expected near '(' 
[2015-08-12 12:57:49] ERROR: Loading script failed: login\s_login.lua:7: ')' expected near '(' 

[FlyingSpoon]

Okay after finding more online resources, and other people's previous fixes.. I nearly got it working.. Now all it does it just keeps creating the same account over and over.. So.. how can I prevent this?

function registrationHandler(username,password) 
handler = mysql_connect("localhost", "root", "", "roleplay") 
    local row = mysql_query(handler, "SELECT * FROM accounts WHERE username=`"..username.."`") 
    if row then 
        outputDebugString("Username already exists") 
        triggerClientEvent(client, "displayLogin", getRootElement()) 
        return 
    end 
  local result = mysql_query(handler, "INSERT INTO accounts (username, password) VALUES ('"..username.."', '"..password.."')") 
    if not result then 
        outputDebugString("Registration failed. "..mysql_error(handler)) 
        triggerClientEvent(client, "displayLogin", getRootElement()) 
        return 
    end 
    triggerClientEvent(client, "displayLogin", getRootElement()) 
    outputChatBox("Registration successful!", client, 0, 255, 0) 
end 
addEvent("onRequestRegister",true) 
addEventHandler("onRequestRegister",root,registrationHandler) 

[GTX]

1. Don't connect to MySQL database every time you register.

2. Free the query result (mysql_free_result)

3. MySQL module is outdated and deprecated. Use DB functions.