Allow multiple mysql connections

script/import_scripts/smf2.rb

@@ -54,8 +54,7 @@ class ImportScripts::Smf2 < ImportScripts::Base
       options.password = HighLine.new.ask('') {|q| q.echo = false }
     end
 
-    @db = Mysql2::Client.new(host: options.host, username: options.username,
-      password: options.password, database: options.database)
+    @default_db_connection = create_db_connection
   end
 
   def execute
@@ -284,15 +283,21 @@ class ImportScripts::Smf2 < ImportScripts::Base
 
   private
 
-  def query(sql, **opts, &block)
-    return __query(sql).to_a                       if opts[:as] == :array
-    return __query(sql, as: :array).first[0]       if opts[:as] == :single
-    return __query(sql, stream: true).each(&block) if block_given?
-    return __query(sql, stream: true)
+  def create_db_connection
+    Mysql2::Client.new(host: options.host, username: options.username,
+      password: options.password, database: options.database)
   end
 
-  def __query(sql, **opts)
-    @db.query(sql.gsub('{prefix}', options.prefix),
+  def query(sql, **opts, &block)
+    db = opts[:connection] || @default_db_connection
+    return __query(db, sql).to_a                       if opts[:as] == :array
+    return __query(db, sql, as: :array).first[0]       if opts[:as] == :single
+    return __query(db, sql, stream: true).each(&block) if block_given?
+    return __query(db, sql, stream: true)
+  end
+
+  def __query(db, sql, **opts)
+    db.query(sql.gsub('{prefix}', options.prefix),
       {symbolize_keys: true, cache_rows: false}.merge(opts))
   end