public OnPlayerConnect(playerid)
{
	new query[128];
	GetPlayerName(playerid, pInfo[playerid][pUsername], MAX_PLAYER_NAME);
	mysql_format(database, query, sizeof query, "SELECT * FROM `users` WHERE `username` = %e LIMIT 1", pInfo[playerid][pUsername]);
	mysql_tquery(database, query);
	pInfo[playerid][playerCache] = cache_save();
	cache_set_active(pInfo[playerid][playerCache]);
	new rowCount;
	cache_get_row_count(rowCount); // -- HERE IS THE PROBLEM I ASSUME
	if(rowCount > 0) {
		new test[256]; // don't mind this it's for debugging
		cache_get_value_name(0, "password", pInfo[playerid][pPass], 65); // ---- HERE IS THE PROBLEM I ASSUME
		format(test, sizeof test, "password: %s", pInfo[playerid][pPass]);  // don't mind this it's for debugging
		SendClientMessage(playerid, -1, test);  // don't mind this it's for debugging
		ShowPlayerDialog(playerid, DIALOG_LOGIN, DIALOG_STYLE_PASSWORD, "Login", "You are registered, type your password to log in.", "Login", "Exit");
	} else 
	{
		ShowPlayerDialog(playerid, DIALOG_REGISTER, DIALOG_STYLE_PASSWORD, "Register", "Type a password to register.", "Register", "Exit");
	}	

	return 1;
}

#include <a_samp>
#include <a_mysql>

#define DIALOG_LOGIN 0
#define DIALOG_REGISTER 1

#define ms_host			"localhost"
#define ms_user			"myname"
#define ms_password		"mypassword"
#define ms_database		"mydbname"

new MySQL:database;

enum playerData {
	pID,
	pUsername[25],
	pPass[65],
	Cache:playerCache
}

new pInfo[MAX_PLAYERS][playerData];


public OnGameModeInit()
{
	database = mysql_connect(ms_host, ms_user, ms_password, ms_database);
	mysql_tquery(database, "CREATE TABLE IF NOT EXISTS `users` (`id` int(11) NOT NULL AUTO_INCREMENT, `username` varchar(24) NOT NULL, `password` char(65) NOT NULL, PRIMARY KEY (`ID`), UNIQUE KEY `USERNAME` (`USERNAME`))");
	return 1;
}

public OnGameModeExit()
{
	for(new i=0; i<MAX_PLAYERS;i++)
	{
		if(IsPlayerConnected(i))
		{
			Kick(i);
		}
	}
	return 1;
}

public OnPlayerConnect(playerid)
{
	new query[128];
	GetPlayerName(playerid, pInfo[playerid][pUsername], MAX_PLAYER_NAME);
	mysql_format(database, query, sizeof query, "SELECT * FROM `users` WHERE `username` = %e LIMIT 1", pInfo[playerid][pUsername]);
	mysql_tquery(database, query);
	pInfo[playerid][playerCache] = cache_save();
	cache_set_active(pInfo[playerid][playerCache]);
	new rowCount;
	cache_get_row_count(rowCount);
	if(rowCount > 0) {
		new test[256];
		cache_get_value_name(0, "password", pInfo[playerid][pPass], 65);
		format(test, sizeof test, "password: %s", pInfo[playerid][pPass]);
		SendClientMessage(playerid, -1, test);
		ShowPlayerDialog(playerid, DIALOG_LOGIN, DIALOG_STYLE_PASSWORD, "Login", "You are registered, type your password to log in.", "Login", "Exit");
	} else 
	{
		ShowPlayerDialog(playerid, DIALOG_REGISTER, DIALOG_STYLE_PASSWORD, "Register", "Type a password to register.", "Register", "Exit");
	}	

	return 1;
}

public OnPlayerDisconnect(playerid, reason)
{
	return 1;
}

public OnDialogResponse(playerid, dialogid, response, listitem, inputtext[])
{
	if(dialogid == DIALOG_LOGIN)
	{
		if(!response) return Kick(playerid);
		new hashedPassword[65];
		SHA256_PassHash(inputtext, "78sdjs86d2h", hashedPassword, sizeof hashedPassword);
		if(strcmp(hashedPassword, pInfo[playerid][pPass]) == 0)
		{
			SendClientMessage(playerid, -1, "Welcome back!");
		} else {
			SendClientMessage(playerid, -1, "Wrong password, try again.");
			ShowPlayerDialog(playerid, DIALOG_LOGIN, DIALOG_STYLE_PASSWORD, "Login", "You are registered, type your password to log in.", "Login", "Exit");
		}
	} else if(dialogid == DIALOG_REGISTER)
	{
		if(!response) return Kick(playerid);
		new query[256];
		new test[256];
		SHA256_PassHash(inputtext, "78sdjs86d2h", pInfo[playerid][pPass], 65);
		format(test, sizeof test, "name: %s, pass: %s", pInfo[playerid][pUsername], pInfo[playerid][pPass]);
		SendClientMessage(playerid, -1, test);
		mysql_format(database, query, sizeof query, "INSERT INTO `users` (`username`, `password`) VALUES ('%e', '%s')", pInfo[playerid][pUsername], pInfo[playerid][pPass]);
		mysql_tquery(database, query);
		ShowPlayerDialog(playerid, DIALOG_LOGIN, DIALOG_STYLE_PASSWORD, "Login", "You are registered, type your password to log in.", "Login", "Exit");
	}
	return 1;
}

public OnPlayerRequestSpawn(playerid)
{
	SetSpawnInfo(playerid, 0, 240,1484.4651,-1742.1217,13.5469,2.9337,0,0,0,0,0,0);
	SpawnPlayer(playerid);
	return 1;
}

[20:29:18] [plugins/mysql] cache_save: no active cache
[20:29:18] [plugins/mysql] cache_set_active: invalid cache id '0'
[20:29:18] [plugins/mysql] cache_get_row_count: no active cache
[20:29:18] [plugins/mysql] cache_get_row_count: no active cache
[20:29:18] [plugins/mysql] error #1054 while executing query "SELECT * FROM `users` WHERE `username` = test2 LIMIT 1": Unknown column 'test2' in 'where clause'