public bool CheckEmailExistance(string email)
{
string query = "SELECT users.email FROM users WHERE users.email = '" + email + "'";
using var connection = MySqlFactory.CreateConnection();
connection.Open();
var command = MySqlFactory.CreateCommand(query, connection);
command.ExecuteNonQuery();
var dataTable = new DataTable();
var adapter = MySqlFactory.CreateDataAdapter(command);
adapter.Fill(dataTable);
return(dataTable.Rows.Count == 1);
}