diff --git a/src/backends/redis/CMakeLists.txt b/src/backends/redis/CMakeLists.txt
index 19f7f05..121572a 100644
--- a/src/backends/redis/CMakeLists.txt
+++ b/src/backends/redis/CMakeLists.txt
@@ -15,6 +15,7 @@ add_library(${PROJECT_NAME} SHARED
 	script.cpp
 	script_manager.cpp
 	async_connection.cpp
+	tag.cpp
 )
 
 target_include_directories(${PROJECT_NAME} SYSTEM
diff --git a/src/backends/redis/backend_redis.cpp b/src/backends/redis/backend_redis.cpp
index 63c6eab..822b4e0 100644
--- a/src/backends/redis/backend_redis.cpp
+++ b/src/backends/redis/backend_redis.cpp
@@ -22,6 +22,7 @@
 #include "helpers/lexical_cast.hpp"
 #include "dindexerConfig.h"
 #include "helpers/stringize.h"
+#include "tag.hpp"
 #include "record_data_adapt.hpp"
 #include <utility>
 #include <yaml-cpp/yaml.h>
@@ -29,7 +30,6 @@
 #include <cstdint>
 #include <boost/range/empty.hpp>
 #include <fstream>
-#include <sstream>
 
 namespace dindb {
 	namespace {
@@ -124,21 +124,7 @@ namespace dindb {
 	}
 
 	void BackendRedis::tag_files (const std::vector<FileIDType>& parFiles, const std::vector<boost::string_ref>& parTags, GroupIDType parSet) {
-		using dinhelp::lexical_cast;
-
-		auto batch = m_redis.make_batch();
-		const std::string set_key = (parSet != InvalidGroupID ? PROGRAM_NAME ":set:" + lexical_cast<std::string>(parSet) : "");
-		for (const auto file_id : parFiles) {
-			for (const auto &tag : parTags) {
-				std::ostringstream oss;
-				oss << PROGRAM_NAME ":tag:" << tag;
-				const std::string tag_key = oss.str();
-				const std::string file_key = PROGRAM_NAME ":file:" + lexical_cast<std::string>(file_id);
-				m_tag_if_in_set.run(batch, std::make_tuple(tag_key, file_key), std::make_tuple(set_key));
-			}
-		}
-
-		batch.throw_if_failed();
+		dindb::tag_files(m_redis, m_tag_if_in_set, parFiles, parTags, parSet);
 	}
 
 	void BackendRedis::tag_files (const std::vector<std::string>& parRegexes, const std::vector<boost::string_ref>& parTags, GroupIDType parSet) {
diff --git a/src/backends/redis/tag.cpp b/src/backends/redis/tag.cpp
new file mode 100644
index 0000000..99fbba1
--- /dev/null
+++ b/src/backends/redis/tag.cpp
@@ -0,0 +1,63 @@
+/* Copyright 2015, 2016, Michele Santullo
+ * This file is part of "dindexer".
+ *
+ * "dindexer" is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * "dindexer" is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with "dindexer".  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "tag.hpp"
+#include "command.hpp"
+#include "dindexerConfig.h"
+#include "helpers/lexical_cast.hpp"
+#include <sstream>
+#include <tuple>
+#include <regex>
+
+namespace dindb {
+	namespace {
+	} //unnamed namespace
+
+	void tag_files (redis::Command& parRedis, redis::Script& parTagIfInSet, const std::vector<uint64_t>& parFiles, const std::vector<boost::string_ref>& parTags, GroupIDType parSet) {
+		using dinhelp::lexical_cast;
+
+		auto batch = parRedis.make_batch();
+		const std::string set_key = (parSet != InvalidGroupID ? PROGRAM_NAME ":set:" + lexical_cast<std::string>(parSet) : "");
+		for (const auto file_id : parFiles) {
+			for (const auto &tag : parTags) {
+				std::ostringstream oss;
+				oss << PROGRAM_NAME ":tag:" << tag;
+				const std::string tag_key = oss.str();
+				const std::string file_key = PROGRAM_NAME ":file:" + lexical_cast<std::string>(file_id);
+				parTagIfInSet.run(batch, std::make_tuple(tag_key, file_key), std::make_tuple(set_key));
+			}
+		}
+
+		batch.throw_if_failed();
+	}
+
+	void tag_files (redis::Command& parRedis, redis::Script& parTagIfInSet, const std::vector<std::string>& parRegexes, const std::vector<boost::string_ref>& parTags, GroupIDType parSet) {
+	}
+
+	void delete_tags (redis::Command& parRedis, redis::Script& parDeleIfInSet, const std::vector<uint64_t>& parFiles, const std::vector<boost::string_ref>& parTags, GroupIDType parSet) {
+	}
+
+	void delete_tags (redis::Command& parRedis, redis::Script& parDeleIfInSet, const std::vector<std::string>& parRegexes, const std::vector<boost::string_ref>& parTags, GroupIDType parSet) {
+	}
+
+	void delete_all_tags (redis::Command& parRedis, redis::Script& parDeleIfInSet, const std::vector<uint64_t>& parFiles, GroupIDType parSet) {
+	}
+
+	void delete_all_tags (redis::Command& parRedis, redis::Script& parDeleIfInSet, const std::vector<std::string>& parRegexes, GroupIDType parSet) {
+	}
+} //namespace dindb
+
diff --git a/src/backends/redis/tag.hpp b/src/backends/redis/tag.hpp
new file mode 100644
index 0000000..1b4b55b
--- /dev/null
+++ b/src/backends/redis/tag.hpp
@@ -0,0 +1,75 @@
+/* Copyright 2015, 2016, Michele Santullo
+ * This file is part of "dindexer".
+ *
+ * "dindexer" is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * "dindexer" is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with "dindexer".  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef id2874EA620CF0415CAF5B005E227BC44B
+#define id2874EA620CF0415CAF5B005E227BC44B
+
+#include "backends/db_backend.hpp"
+#include <vector>
+#include <boost/utility/string_ref.hpp>
+#include <cstdint>
+
+namespace redis {
+	class Command;
+	class Script;
+} //namespace redis
+
+namespace dindb {
+	void tag_files (
+		redis::Command& parRedis,
+		redis::Script& parTagIfInSet,
+		const std::vector<uint64_t>& parFiles,
+		const std::vector<boost::string_ref>& parTags,
+		GroupIDType parSet
+	);
+	void tag_files (
+		redis::Command& parRedis,
+		redis::Script& parTagIfInSet,
+		const std::vector<std::string>& parRegexes,
+		const std::vector<boost::string_ref>& parTags,
+		GroupIDType parSet
+	);
+
+	void delete_tags (
+		redis::Command& parRedis,
+		redis::Script& parDeleIfInSet,
+		const std::vector<uint64_t>& parFiles,
+		const std::vector<boost::string_ref>& parTags,
+		GroupIDType parSet
+	);
+	void delete_tags (
+		redis::Command& parRedis,
+		redis::Script& parDeleIfInSet,
+		const std::vector<std::string>& parRegexes,
+		const std::vector<boost::string_ref>& parTags,
+		GroupIDType parSet
+	);
+	void delete_all_tags (
+		redis::Command& parRedis,
+		redis::Script& parDeleIfInSet,
+		const std::vector<uint64_t>& parFiles,
+		GroupIDType parSet
+	);
+	void delete_all_tags (
+		redis::Command& parRedis,
+		redis::Script& parDeleIfInSet,
+		const std::vector<std::string>& parRegexes,
+		GroupIDType parSet
+	);
+} //namespace dindb
+
+#endif