Start on a simpler SQLite interface

4 files changed, 389 insertions, 780 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2fae0670..5829988a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -161,6 +161,7 @@ vala_precompile(FEEDREADER ${FEEDREADER_NAME}
 	src/Structs.vala
 	src/Utils.vala
 	src/QueryBuilder.vala
+	src/SQLite.vala
 	src/ContentGrabber/grabberUtils.vala
 	src/ContentGrabber/stringPair.vala
 	src/Model/Feed.vala
diff --git a/src/DataBaseReadOnly.vala b/src/DataBaseReadOnly.vala
index 7a0b97d0..19fbaed0 100644
--- a/src/DataBaseReadOnly.vala
+++ b/src/DataBaseReadOnly.vala
@@ -15,289 +15,154 @@
 
 public class FeedReader.DataBaseReadOnly : GLib.Object {
 
-	protected Sqlite.Database sqlite_db;
+	protected SQLite m_db;
 
-	public DataBaseReadOnly(string dbFile = "feedreader-%01i.db".printf(Constants.DB_SCHEMA_VERSION))
+	public DataBaseReadOnly(string db_file = "feedreader-%01i.db".printf(Constants.DB_SCHEMA_VERSION))
 	{
 		Sqlite.config(Sqlite.Config.LOG, errorLogCallback);
-		string db_path = GLib.Environment.get_user_data_dir() + "/feedreader/data/";
-		var path = GLib.File.new_for_path(db_path);
-		if(!path.query_exists())
-		{
-			try
-			{
-				path.make_directory_with_parents();
-			}
-			catch(GLib.Error e)
-			{
-				Logger.error("Can't create directory for database: %s".printf(e.message));
-			}
-		}
+		string db_path = GLib.Environment.get_user_data_dir() + "/feedreader/data/" + db_file;
 
-		Logger.debug(@"Opening Database: $db_path$dbFile");
-		int rc = Sqlite.Database.open_v2(db_path + dbFile, out sqlite_db);
-		if(rc != Sqlite.OK)
-			Logger.error("Can't open database: %d: %s".printf(sqlite_db.errcode(), sqlite_db.errmsg()));
-
-		sqlite_db.busy_timeout(1000);
-		sqlite_db.update_hook(watchDog);
+		Logger.debug(@"Opening Database: $db_path");
+		m_db = new SQLite(db_path);
 	}
 
-	private void watchDog(Sqlite.Action action, string dbname, string table, int64 rowID)
+	private void errorLogCallback(int code, string msg)
 	{
-		if(action == Sqlite.Action.DELETE && !table.has_prefix("fts_"))
-		{
-			Logger.warning("DELETING rowID: %s from  table: %s and db: %s".printf(rowID.to_string(), table, dbname));
-		}
+		Logger.error(@"dbErrorLog: $code: $msg");
 	}
 
-	private void errorLogCallback(int eCode, string msg)
+	// Generate enough placeholders for n parameters
+	private static string n_params(int n)
 	{
-		Logger.error("dbErrorLog: " + eCode.to_string() + ": " + msg);
+		StringBuilder s = new StringBuilder.sized(n * 2 - 1);
+		for(int i = 0; i < n; ++i)
+		{
+			if(i != 0)
+				s.append(",");
+			s.append("?");
+		}
+		return s.str;
 	}
 
 	public void init()
 	{
 		Logger.debug("init database");
-		executeSQL("PRAGMA journal_mode = WAL");
-		executeSQL("PRAGMA page_size = 4096");
-
-		executeSQL(					"""CREATE  TABLE  IF NOT EXISTS "main"."feeds"
-										(
-											"feed_id" TEXT PRIMARY KEY NOT NULL UNIQUE,
-											"name" TEXT NOT NULL,
-											"url" TEXT NOT NULL,
-											"category_id" TEXT,
-											"subscribed" INTEGER DEFAULT 1,
-											"xmlURL" TEXT,
-											"iconURL" TEXT
-										)""");
-
-		executeSQL(					"""CREATE  TABLE  IF NOT EXISTS "main"."categories"
-										(
-											"categorieID" TEXT PRIMARY KEY NOT NULL UNIQUE,
-											"title" TEXT NOT NULL,
-											"orderID" INTEGER,
-											"exists" INTEGER,
-											"Parent" TEXT,
-											"Level" INTEGER
-											)""");
-
-		executeSQL(					"""CREATE  TABLE  IF NOT EXISTS "main"."articles"
-										(
-											"articleID" TEXT PRIMARY KEY NOT NULL UNIQUE,
-											"feedID" TEXT NOT NULL,
-											"title" TEXT NOT NULL,
-											"author" TEXT,
-											"url" TEXT NOT NULL,
-											"html" TEXT NOT NULL,
-											"preview" TEXT NOT NULL,
-											"unread" INTEGER NOT NULL,
-											"marked" INTEGER NOT NULL,
-											"tags" TEXT,
-											"date" INTEGER NOT NULL,
-											"guidHash" TEXT,
-											"lastModified" INTEGER,
-											"media" TEXT,
-											"contentFetched" INTEGER NOT NULL
-										)""");
-
-		executeSQL(					   """CREATE  TABLE  IF NOT EXISTS "main"."tags"
-										(
-											"tagID" TEXT PRIMARY KEY NOT NULL UNIQUE,
-											"title" TEXT NOT NULL,
-											"exists" INTEGER,
-											"color" INTEGER
-										)""");
-
-		executeSQL(					   """CREATE  TABLE  IF NOT EXISTS "main"."CachedActions"
-										(
-											"action" INTEGER NOT NULL,
-											"id" TEXT NOT NULL,
-											"argument" INTEGER
-										)""");
-
-		executeSQL(			 			"""CREATE INDEX IF NOT EXISTS "index_articles" ON "articles" ("feedID" DESC, "unread" ASC, "marked" ASC)""");
-		executeSQL(						"""CREATE VIRTUAL TABLE IF NOT EXISTS fts_table USING fts4 (content='articles', articleID, preview, title, author)""");
-	}
-
-	protected void executeSQL(string sql, Sqlite.Callback? callback = null)
-	{
-		string errmsg;
-		int ec = sqlite_db.exec(sql, null, out errmsg);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(sql);
-			Logger.error(errmsg);
-		}
+		m_db.simple_query("PRAGMA journal_mode = WAL");
+		m_db.simple_query("PRAGMA page_size = 4096");
+
+		m_db.simple_query("""
+			CREATE  TABLE  IF NOT EXISTS "main"."feeds"
+			(
+				"feed_id" TEXT PRIMARY KEY NOT NULL UNIQUE,
+				"name" TEXT NOT NULL,
+				"url" TEXT NOT NULL,
+				"category_id" TEXT,
+				"subscribed" INTEGER DEFAULT 1,
+				"xmlURL" TEXT,
+				"iconURL" TEXT
+			)
+		""");
+
+		m_db.simple_query("""
+			CREATE  TABLE  IF NOT EXISTS "main"."categories"
+			(
+				"categorieID" TEXT PRIMARY KEY NOT NULL UNIQUE,
+				"title" TEXT NOT NULL,
+				"orderID" INTEGER,
+				"exists" INTEGER,
+				"Parent" TEXT,
+				"Level" INTEGER
+			)
+		""");
+
+		m_db.simple_query("""
+			CREATE  TABLE  IF NOT EXISTS "main"."articles"
+			(
+				"articleID" TEXT PRIMARY KEY NOT NULL UNIQUE,
+				"feedID" TEXT NOT NULL,
+				"title" TEXT NOT NULL,
+				"author" TEXT,
+				"url" TEXT NOT NULL,
+				"html" TEXT NOT NULL,
+				"preview" TEXT NOT NULL,
+				"unread" INTEGER NOT NULL,
+				"marked" INTEGER NOT NULL,
+				"tags" TEXT,
+				"date" INTEGER NOT NULL,
+				"guidHash" TEXT,
+				"lastModified" INTEGER,
+				"media" TEXT,
+				"contentFetched" INTEGER NOT NULL
+			)
+		""");
+
+		m_db.simple_query("""
+			CREATE  TABLE  IF NOT EXISTS "main"."tags"
+			(
+				"tagID" TEXT PRIMARY KEY NOT NULL UNIQUE,
+				"title" TEXT NOT NULL,
+				"exists" INTEGER,
+				"color" INTEGER
+			)
+		""");
+
+		m_db.simple_query("""
+			CREATE  TABLE  IF NOT EXISTS "main"."CachedActions"
+			(
+				"action" INTEGER NOT NULL,
+				"id" TEXT NOT NULL,
+				"argument" INTEGER
+			)
+		""");
+
+		m_db.simple_query("""
+			CREATE INDEX IF NOT EXISTS "index_articles"
+			ON "articles" ("feedID" DESC, "unread" ASC, "marked" ASC)
+		""");
+		m_db.simple_query("""
+			CREATE VIRTUAL TABLE IF NOT EXISTS fts_table
+			USING fts4 (content='articles', articleID, preview, title, author)
+		""");
 	}
 
 	public bool uninitialized()
 	{
 		string query = "SELECT count(*) FROM sqlite_master WHERE type='table' AND name='articles'";
-
-		int count = -1;
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query, query.length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query);
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		while(stmt.step() == Sqlite.ROW)
-		{
-			count = stmt.column_int(0);
-		}
-		stmt.reset();
-
-		if(count == 0)
-		{
-			Logger.warning("database uninitialized");
-			return true;
-		}
-		else if(count == 1)
-		{
-			Logger.debug("database already initialized");
-			return false;
-		}
-
-		return true;
+		var rows = m_db.execute(query);
+		assert(rows.size == 1 && rows[0].size == 1);
+		return (int)rows[0][0] == 0;
 	}
 
 	public bool isEmpty()
 	{
-		if(!isTableEmpty("articles"))
-		{
-			return false;
-		}
-
-		if(!isTableEmpty("categories"))
-		{
-			return false;
-		}
-
-		if(!isTableEmpty("feeds"))
-		{
-			return false;
-		}
-
-		if(!isTableEmpty("tags"))
-		{
-			return false;
-		}
-
-		return true;
+		return isTableEmpty("articles")
+			&& isTableEmpty("categories")
+			&& isTableEmpty("feeds")
+			&& isTableEmpty("tags");
 	}
 
 	public bool isTableEmpty(string table)
 	{
-		var query = new QueryBuilder(QueryType.SELECT, table);
-		query.selectField("count(*)");
-		query.build();
-
-		int count = -1;
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		while(stmt.step() == Sqlite.ROW)
-		{
-			count = stmt.column_int(0);
-		}
-		stmt.reset();
-
-		if(count > 0)
-		{
-			Logger.debug(@"Table $table is not empty");
-			return false;
-		}
-		else
-		{
-			Logger.debug(@"Table $table is empty");
-			return true;
-		}
-	}
-
-	public int getArticelCount()
-	{
-		int count = -1;
-
-		var query = new QueryBuilder(QueryType.SELECT, "articles");
-		query.selectField("count(*)");
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		int cols = stmt.column_count ();
-		while(stmt.step() == Sqlite.ROW)
-		{
-			for(int i = 0; i < cols; i++)
-			{
-				count = stmt.column_int(i);
-			}
-		}
-		stmt.reset();
-
-		return count;
+		var query = @"SELECT COUNT(*) FROM $table";
+		var rows = m_db.execute(query);
+		assert(rows.size == 1 && rows[0].size == 1);
+		return (int)rows[0][0] == 0;
 	}
 
 	public uint get_unread_total()
 	{
-		var query = new QueryBuilder(QueryType.SELECT, "articles");
-		query.selectField("count(*)");
-		query.addEqualsCondition("unread", ArticleStatus.UNREAD.to_string());
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		uint unread = 0;
-		while (stmt.step () == Sqlite.ROW) {
-			unread = stmt.column_int(0);
-		}
-
-		stmt.reset ();
-		return unread;
+		var query = "SELECT COUNT(*) FROM articles WHERE unread = ?";
+		var rows = m_db.execute(query, ArticleStatus.UNREAD.to_string());
+		assert(rows.size == 1 && rows[0].size == 1);
+		return (int)rows[0][0];
 	}
 
 	public uint get_marked_total()
 	{
-		var query = new QueryBuilder(QueryType.SELECT, "articles");
-		query.selectField("count(*)");
-		query.addEqualsCondition("marked", ArticleStatus.MARKED.to_string());
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		uint marked = 0;
-		while (stmt.step () == Sqlite.ROW) {
-			marked = stmt.column_int(0);
-		}
-
-		stmt.reset ();
-		return marked;
+		var query = "SELECT COUNT(*) FROM articles WHERE marked = ?";
+		var rows = m_db.execute(query, ArticleStatus.MARKED.to_string());
+		assert(rows.size == 1 && rows[0].size == 1);
+		return (int)rows[0][0];
 	}
 
 	public uint get_unread_uncategorized()
@@ -308,13 +173,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition(getUncategorizedFeedsQuery());
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int unread = 0;
 		while (stmt.step() == Sqlite.ROW) {
@@ -332,13 +191,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition(getUncategorizedFeedsQuery());
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int marked = 0;
 		while (stmt.step() == Sqlite.ROW) {
@@ -355,13 +208,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition("instr(tagID, \"global.\") = 0");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int tagCount = 0;
 		while (stmt.step () == Sqlite.ROW) {
@@ -374,102 +221,30 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 
 	public bool tag_still_used(Tag tag)
 	{
-		var query = new QueryBuilder(QueryType.SELECT, "main.articles");
-		query.selectField("count(*)");
-		query.addCustomCondition("instr(tags, \"%s\") > 0".printf(tag.getTagID()));
-		query.limit(2);
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error("tag_still_used: " + sqlite_db.errmsg());
-		}
-
-		while (stmt.step () == Sqlite.ROW) {
-			if(stmt.column_int(0) > 1)
-				return true;
-		}
-
-		return false;
-	}
-
-	public string getFeedName(string feedID)
-	{
-		string result = _("unknown Feed");
-
-		if(feedID == "")
-			return result;
-
-		var query = new QueryBuilder(QueryType.SELECT, "feeds");
-		query.selectField("name");
-		query.addEqualsCondition("feed_id", feedID, true, true);
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		while(stmt.step() == Sqlite.ROW)
-		{
-			result = stmt.column_text(0);
-		}
-
-		return result;
+		var query = "SELECT 1 FROM main.articles WHERE instr(tagID, ?) > 0 LIMIT 1";
+		var rows = m_db.execute(query, tag.getTagID());
+		return rows.size > 0;
 	}
 
-
-	public string? getTagName(string tagID)
+	public string? getTagName(string tag_id)
 	{
-		var query = new QueryBuilder(QueryType.SELECT, "tags");
-		query.selectField("title");
-		query.addEqualsCondition("tagID", tagID, true, true);
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		string result = null;
-
-		while (stmt.step () == Sqlite.ROW) {
-			result = stmt.column_text(0);
-		}
-
-		return result;
+		var query = "SELECT title FROM tags WHERE tagID = ?";
+		var rows = m_db.execute(query, tag_id);
+		assert(rows.size == 0 || (rows.size == 1 && rows[0].size == 1));
+		if(rows.size == 1)
+			return (string)rows[0][0];
+		return _("Unknown tag");
 	}
 
 	public int getLastModified()
 	{
-		var query = new QueryBuilder(QueryType.SELECT, "articles");
-		query.selectField("MAX(lastModified)");
-		query.build();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-		int result = 0;
-
-		while (stmt.step () == Sqlite.ROW) {
-			result = stmt.column_int(0);
-		}
-
-		return result;
+		var query = "SELECT MAX(lastModified) FROM articles";
+		var rows = m_db.execute(query);
+		assert(rows.size == 0 || (rows.size == 1 && rows[0].size == 1));
+		if(rows.size == 1 && rows[0][0] != null)
+			return (int)rows[0][0];
+		else
+			return 0;
 	}
 
 
@@ -483,13 +258,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("categorieID", catID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		string result = "";
 
@@ -511,13 +280,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("title", catname, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		string? result = null;
 
@@ -537,13 +300,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("preview", "", false, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int result = 1;
 
@@ -583,13 +340,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		}
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		var articles = new Gee.ArrayList<Article>();
 		while (stmt.step () == Sqlite.ROW)
@@ -626,13 +377,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addRangeConditionString("articleID", ids);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		var articles = new Gee.HashMap<string, Article>();
 
@@ -656,13 +401,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("articleID", articleID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while(stmt.step() == Sqlite.ROW)
 		{
@@ -696,14 +435,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.selectField("max(Level)");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 		while (stmt.step () == Sqlite.ROW) {
 			maxCatLevel = stmt.column_int(0);
 		}
@@ -723,13 +455,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition(getUncategorizedQuery());
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			int count = stmt.column_int(0);
@@ -746,14 +472,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.selectField("count(*)");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 		while (stmt.step () == Sqlite.ROW) {
 			int count = stmt.column_int(0);
 
@@ -768,13 +487,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 	{
 		int result = 0;
 		string query = "SELECT EXISTS(SELECT 1 FROM articles WHERE articleID = \"" + articleID + "\" LIMIT 1)";
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query, query.length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query);
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query);
 
 		while (stmt.step () == Sqlite.ROW) {
 			result = stmt.column_int(0);
@@ -789,14 +502,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 	{
 		int result = 0;
 		string query = "SELECT EXISTS(SELECT 1 FROM categories WHERE categorieID = \"" + catID + "\" LIMIT 1)";
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query, query.length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query);
-			Logger.error(sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query);
 		while (stmt.step () == Sqlite.ROW) {
 			result = stmt.column_int(0);
 		}
@@ -816,13 +522,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition("date > \"%s\"".printf(date));
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			result = stmt.column_int(0);
@@ -911,15 +611,8 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 
 		query2.orderBy(orderBy, desc);
 		query2.build();
-		query2.print();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query2.get(), query2.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query2.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query2.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			result = stmt.column_int(0);
@@ -928,7 +621,6 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		return result;
 	}
 
-
 	public Gee.List<string> getFeedIDofCategorie(string categorieID)
 	{
 		var feedIDs = new Gee.ArrayList<string>();
@@ -937,13 +629,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.selectField("feed_id, category_id");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step() == Sqlite.ROW) {
 			string catString = stmt.column_text(1);
@@ -996,13 +682,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition(getUncategorizedQuery());
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		string feedIDs = "";
 		while (stmt.step () == Sqlite.ROW) {
@@ -1016,13 +696,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 	public string getFeedIDofArticle(string articleID)
 	{
 		string query = "SELECT feedID FROM \"main\".\"articles\" WHERE \"articleID\" = " + "\"" + articleID + "\"";
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query, query.length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query);
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query);
 
 		string id = "";
 		while (stmt.step () == Sqlite.ROW) {
@@ -1041,13 +715,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("rowid", "%s".printf(getMaxID("articles", "rowid")));
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			result = stmt.column_text(0);
@@ -1062,13 +730,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.selectField("max(%s)".printf(field));
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW)
 		{
@@ -1086,13 +748,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.limit(1);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error("feed_exists: " + sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			if(stmt.column_int(0) > 1)
@@ -1109,13 +765,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("feed_id", feedID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while(stmt.step () == Sqlite.ROW)
 		{
@@ -1146,13 +796,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		}
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			string feedID = stmt.column_text(0);
@@ -1187,13 +831,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("feedID", feedID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			count = (uint)stmt.column_int(0);
@@ -1211,13 +849,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("feedID", feedID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			count = (uint)stmt.column_int(0);
@@ -1239,13 +871,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		}
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			string feedID = stmt.column_text(0);
@@ -1269,13 +895,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("categorieID", catID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			var tmpcategory = new Category(
@@ -1303,13 +923,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addCustomCondition("instr(tagID, \"global.\") = 0");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			tmpTag = new Tag(stmt.column_text(0), stmt.column_text(1), stmt.column_int(3));
@@ -1328,13 +942,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("tagID", tagID, true, true);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			tmpTag = new Tag(stmt.column_text(0), stmt.column_text(1), stmt.column_int(3));
@@ -1364,13 +972,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.selectField("count(*)");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while (stmt.step () == Sqlite.ROW) {
 			count = stmt.column_int(0);
@@ -1413,13 +1015,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while(stmt.step () == Sqlite.ROW)
 		{
@@ -1455,14 +1051,7 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.addEqualsCondition("contentFetched", "0", true, false);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		var tmp = new Gee.LinkedList<Article>();
 		while (stmt.step () == Sqlite.ROW)
@@ -1574,17 +1163,8 @@ public class FeedReader.DataBaseReadOnly : GLib.Object {
 		query.limit(limit);
 		query.offset(offset);
 		query.build();
-		query.print();
-
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
 
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		var tmp = new Gee.LinkedList<Article>();
 		while (stmt.step () == Sqlite.ROW)
diff --git a/src/DataBaseWriteAccess.vala b/src/DataBaseWriteAccess.vala
index 29d77d7e..c987a19c 100644
--- a/src/DataBaseWriteAccess.vala
+++ b/src/DataBaseWriteAccess.vala
@@ -41,28 +41,21 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 
 	public void checkpoint()
 	{
-		sqlite_db.wal_checkpoint("");
+		m_db.checkpoint();
 	}
 
 	public bool resetDB()
 	{
 		Logger.warning("resetDB");
-		executeSQL("DROP TABLE main.feeds");
-		executeSQL("DROP TABLE main.categories");
-		executeSQL("DROP TABLE main.articles");
-		executeSQL("DROP TABLE main.tags");
-		executeSQL("DROP TABLE main.fts_table");
-		executeSQL("VACUUM");
+		m_db.simple_query("DROP TABLE main.feeds");
+		m_db.simple_query("DROP TABLE main.categories");
+		m_db.simple_query("DROP TABLE main.articles");
+		m_db.simple_query("DROP TABLE main.tags");
+		m_db.simple_query("DROP TABLE main.fts_table");
+		m_db.simple_query("VACUUM");
 
 		string query = "PRAGMA INTEGRITY_CHECK";
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query, query.length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query);
-			Logger.error(sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query);
 
 		int cols = stmt.column_count ();
 		while (stmt.step () == Sqlite.ROW) {
@@ -80,12 +73,12 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 
 	public void updateFTS()
 	{
-		executeSQL("INSERT INTO fts_table(fts_table) VALUES('rebuild')");
+		m_db.simple_query("INSERT INTO fts_table(fts_table) VALUES('rebuild')");
 	}
 
 	public void springCleaning()
 	{
-		executeSQL("VACUUM");
+		m_db.simple_query("VACUUM");
 		var now = new DateTime.now_local();
 		Settings.state().set_int("last-spring-cleaning", (int)now.to_unix());
 	}
@@ -103,16 +96,8 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			query.addCustomCondition(@"rowid BETWEEN 1 AND (SELECT rowid FROM articles ORDER BY rowid DESC LIMIT 1 OFFSET $syncCount)");
 		}
 		query.build();
-		query.print();
-
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
 
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 		while (stmt.step () == Sqlite.ROW) {
 			delete_article(stmt.column_text(0), stmt.column_text(1));
 		}
@@ -121,7 +106,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 	private void delete_article(string articleID, string feedID)
 	{
 		Logger.info("Deleting article \"%s\"".printf(articleID));
-		executeSQL("DELETE FROM main.articles WHERE articleID = \"" + articleID + "\"");
+		m_db.simple_query("DELETE FROM main.articles WHERE articleID = \"" + articleID + "\"");
 		string folder_path = GLib.Environment.get_user_data_dir() + "/feedreader/data/images/%s/%s/".printf(feedID, articleID);
 		Utils.remove_directory(folder_path);
 	}
@@ -130,7 +115,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 	{
 		var query = new QueryBuilder(QueryType.DELETE, "main.tags");
 		query.addEqualsCondition("tagID", tag.getTagID(), true, true);
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 
 		query = new QueryBuilder(QueryType.SELECT, "main.articles");
 		query.selectField("tags");
@@ -138,13 +123,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.addCustomCondition("instr(tags, \"%s\") > 0".printf(tag.getTagID()));
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while(stmt.step () == Sqlite.ROW)
 		{
@@ -156,13 +135,13 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			query = new QueryBuilder(QueryType.UPDATE, "main.articles");
 			query.updateValuePair("tags", "\"%s\"".printf(StringUtils.join(tags, ",")));
 			query.addEqualsCondition("articleID", articleID, true, true);
-			executeSQL(query.build());
+			m_db.simple_query(query.build());
 		}
 	}
 
 	public void write_feeds(Gee.List<Feed> feeds)
 	{
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var query = new QueryBuilder(QueryType.INSERT_OR_REPLACE, "main.feeds");
 		query.insertValuePair("feed_id", "$FEEDID");
@@ -174,15 +153,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.insertValuePair("iconURL", "$ICONURL");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error("DataBase: write_feeds - " + query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int feedID_pos   = stmt.bind_parameter_index("$FEEDID");
 		int feedName_pos = stmt.bind_parameter_index("$FEEDNAME");
@@ -218,7 +189,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 	public void write_tag(Tag tag)
@@ -230,7 +201,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 
 	public void write_tags(Gee.List<Tag> tags)
 	{
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var query = new QueryBuilder(QueryType.INSERT_OR_IGNORE, "main.tags");
 		query.insertValuePair("tagID", "$TAGID");
@@ -239,13 +210,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.insertValuePair("color", "$COLOR");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error("DataBase: write_tags - " + query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int tagID_position = stmt.bind_parameter_index("$TAGID");
 		int label_position = stmt.bind_parameter_index("$LABEL");
@@ -265,7 +230,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset ();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 	public void update_tag(Tag tag)
@@ -280,20 +245,20 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			var query2 = new QueryBuilder(QueryType.UPDATE, "tags");
 			query2.updateValuePair("tagID", newID, true);
 			query2.addEqualsCondition("tagID", tag.getTagID(), true, true);
-			executeSQL(query2.build());
+			m_db.simple_query(query2.build());
 			query2.print();
 
 			var query3 = new QueryBuilder(QueryType.UPDATE, "articles");
 			query3.updateValuePair("tags", "replace(tags, '%s', '%s')".printf(tag.getTagID(), newID));
 			query3.addCustomCondition("instr(tags, '%s')".printf(tag.getTagID()));
-			executeSQL(query3.build());
+			m_db.simple_query(query3.build());
 			query3.print();
 		}
 	}
 
 	public void update_tags(Gee.List<Tag> tags)
 	{
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var query = new QueryBuilder(QueryType.UPDATE, "main.tags");
 		query.updateValuePair("title", "$TITLE");
@@ -301,13 +266,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.addEqualsCondition("tagID", "$TAGID");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error("DataBase: update_tags - " + query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int title_position = stmt.bind_parameter_index("$TITLE");
 		int tagID_position = stmt.bind_parameter_index("$TAGID");
@@ -322,13 +281,13 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset ();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 
 	public void write_categories(Gee.List<Category> categories)
 	{
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var query = new QueryBuilder(QueryType.INSERT_OR_REPLACE, "main.categories");
 		query.insertValuePair("categorieID", "$CATID");
@@ -339,14 +298,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.insertValuePair("Level", "$LEVEL");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error("DataBase: write_categories - " + query.get());
-			Logger.error(sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int catID_position       = stmt.bind_parameter_index("$CATID");
 		int feedName_position    = stmt.bind_parameter_index("$FEEDNAME");
@@ -371,7 +323,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset ();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 	public void updateArticlesByID(Gee.List<string> ids, string field)
@@ -382,10 +334,10 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			reset_query.updateValuePair(field, ArticleStatus.READ.to_string());
 		else if(field == "marked")
 			reset_query.updateValuePair(field, ArticleStatus.UNMARKED.to_string());
-		executeSQL(reset_query.build());
+		m_db.simple_query(reset_query.build());
 
 
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		// then reapply states of the synced articles
 		var update_query = new QueryBuilder(QueryType.UPDATE, "main.articles");
@@ -398,14 +350,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		update_query.addEqualsCondition("articleID", "$ARTICLEID");
 		update_query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (update_query.get(), update_query.get().length, out stmt);
-
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(update_query.get());
-			Logger.error("updateArticlesByID: " + sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(update_query.get());
 
 		int articleID_position = stmt.bind_parameter_index("$ARTICLEID");
 		assert (articleID_position > 0);
@@ -418,7 +363,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 	public void writeContent(Article article)
@@ -430,14 +375,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		update_query.addEqualsCondition("articleID", article.getArticleID(), true, true);
 		update_query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(update_query.get(), update_query.get().length, out stmt);
-
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(update_query.get());
-			Logger.error("writeContent: " + sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(update_query.get());
 
 		int html_position = stmt.bind_parameter_index("$HTML");
 		int preview_position = stmt.bind_parameter_index("$PREVIEW");
@@ -459,17 +397,9 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		update_articles(list);
 	}
 
-	// public void update_article(Article article, string field, int field_value)
-	// {
-	// 	var query = new QueryBuilder(QueryType.UPDATE, "main.articles");
-	// 	query.updateValuePair(field, field_value.to_string());
-	// 	query.addEqualsCondition("articleID", article.getArticleID(), true, true);
-	// 	executeSQL(query.build());
-	// }
-
 	public void update_articles(Gee.List<Article> articles)
 	{
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var update_query = new QueryBuilder(QueryType.UPDATE, "main.articles");
 		update_query.updateValuePair("unread", "$UNREAD");
@@ -479,14 +409,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		update_query.addEqualsCondition("articleID", "$ARTICLEID", true, false);
 		update_query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(update_query.get(), update_query.get().length, out stmt);
-
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(update_query.get());
-			Logger.error("update_articles: " + sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(update_query.get());
 
 		int unread_position = stmt.bind_parameter_index("$UNREAD");
 		int marked_position = stmt.bind_parameter_index("$MARKED");
@@ -521,7 +444,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 
@@ -530,7 +453,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		Utils.generatePreviews(articles);
 		Utils.checkHTML(articles);
 
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var query = new QueryBuilder(QueryType.INSERT_OR_IGNORE, "main.articles");
 		query.insertValuePair("articleID", "$ARTICLEID");
@@ -550,16 +473,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.insertValuePair("contentFetched", "0");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error("write_articles: " + sqlite_db.errmsg());
-		}
-
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int articleID_position = stmt.bind_parameter_index("$ARTICLEID");
 		int feedID_position = stmt.bind_parameter_index("$FEEDID");
@@ -636,7 +550,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			stmt.reset();
 		}
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 	public void markCategorieRead(string catID)
@@ -644,7 +558,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		var query = new QueryBuilder(QueryType.UPDATE, "main.articles");
 		query.updateValuePair("unread", ArticleStatus.READ.to_string());
 		query.addRangeConditionString("feedID", getFeedIDofCategorie(catID));
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 	}
 
 	public void markFeedRead(string feedID)
@@ -652,48 +566,48 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		var query = new QueryBuilder(QueryType.UPDATE, "main.articles");
 		query.updateValuePair("unread", ArticleStatus.READ.to_string());
 		query.addEqualsCondition("feedID", feedID, true, true);
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 	}
 
 	public void markAllRead()
 	{
 		var query1 = new QueryBuilder(QueryType.UPDATE, "main.articles");
 		query1.updateValuePair("unread", ArticleStatus.READ.to_string());
-		executeSQL(query1.build());
+		m_db.simple_query(query1.build());
 	}
 
 	public void reset_subscribed_flag()
 	{
-		executeSQL("UPDATE main.feeds SET \"subscribed\" = 0");
+		m_db.simple_query("UPDATE main.feeds SET \"subscribed\" = 0");
 	}
 
 	public void reset_exists_tag()
 	{
-		executeSQL("UPDATE main.tags SET \"exists\" = 0");
+		m_db.simple_query("UPDATE main.tags SET \"exists\" = 0");
 	}
 
 	public void reset_exists_flag()
 	{
-		executeSQL("UPDATE main.categories SET \"exists\" = 0");
+		m_db.simple_query("UPDATE main.categories SET \"exists\" = 0");
 	}
 
 	public void delete_unsubscribed_feeds()
 	{
 		Logger.warning("DataBase: Deleting unsubscribed feeds");
-		executeSQL("DELETE FROM main.feeds WHERE \"subscribed\" = 0");
+		m_db.simple_query("DELETE FROM main.feeds WHERE \"subscribed\" = 0");
 	}
 
 
 	public void delete_nonexisting_categories()
 	{
 		Logger.warning("DataBase: Deleting nonexisting categories");
-		executeSQL("DELETE FROM main.categories WHERE \"exists\" = 0");
+		m_db.simple_query("DELETE FROM main.categories WHERE \"exists\" = 0");
 	}
 
 	public void delete_nonexisting_tags()
 	{
 		Logger.warning("DataBase: Deleting nonexisting tags");
-		executeSQL("DELETE FROM main.tags WHERE \"exists\" = 0");
+		m_db.simple_query("DELETE FROM main.tags WHERE \"exists\" = 0");
 	}
 
 	public void delete_articles_without_feed()
@@ -704,14 +618,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.addEqualsCondition("subscribed", "0", true, false);
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error("DataBase: delete_articles_without_feed: %d: %s".printf(sqlite_db.errcode(), sqlite_db.errmsg()));
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 		while(stmt.step () == Sqlite.ROW)
 		{
 			delete_articles(stmt.column_text(0));
@@ -721,14 +628,14 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 	public void delete_articles(string feedID)
 	{
 		Logger.warning("DataBase: Deleting all articles of feed \"%s\"".printf(feedID));
-		executeSQL("DELETE FROM main.articles WHERE feedID = \"" + feedID + "\"");
+		m_db.simple_query("DELETE FROM main.articles WHERE feedID = \"" + feedID + "\"");
 		string folder_path = GLib.Environment.get_user_data_dir() + "/feedreader/data/images/%s/".printf(feedID);
 		Utils.remove_directory(folder_path);
 	}
 
 	public void delete_category(string catID)
 	{
-		executeSQL("DELETE FROM main.categories WHERE categorieID = \"" + catID + "\"");
+		m_db.simple_query("DELETE FROM main.categories WHERE categorieID = \"" + catID + "\"");
 
 		if(FeedServer.get_default().supportMultiCategoriesPerFeed())
 		{
@@ -737,29 +644,22 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			query.addCustomCondition("instr(category_id, \"%s\") > 0".printf(catID));
 			query.build();
 
-			Sqlite.Statement stmt;
-			int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-			if (ec != Sqlite.OK)
-			{
-				Logger.error(query.get());
-				Logger.error("delete_articles: " + sqlite_db.errmsg());
-			}
-
+			Sqlite.Statement stmt = m_db.prepare(query.get());
 			while(stmt.step () == Sqlite.ROW)
 			{
 				string feedID = stmt.column_text(0);
 				string catIDs = stmt.column_text(0).replace(catID + ",", "");
 
-				executeSQL("UPDATE main.feeds set category_id = \"" + catIDs + "\" WHERE feed_id = \"" + feedID + "\"");
+				m_db.simple_query("UPDATE main.feeds set category_id = \"" + catIDs + "\" WHERE feed_id = \"" + feedID + "\"");
 			}
 		}
 		else
 		{
-			executeSQL("UPDATE main.feeds set category_id = \"%s\" WHERE category_id = \"%s\"".printf(FeedServer.get_default().uncategorizedID(), catID));
+			m_db.simple_query("UPDATE main.feeds set category_id = \"%s\" WHERE category_id = \"%s\"".printf(FeedServer.get_default().uncategorizedID(), catID));
 
 			if(FeedServer.get_default().supportMultiLevelCategories())
 			{
-				executeSQL("UPDATE main.categories set Parent = \"-2\" WHERE categorieID = \"" + catID + "\"");
+				m_db.simple_query("UPDATE main.categories set Parent = \"-2\" WHERE categorieID = \"" + catID + "\"");
 			}
 		}
 	}
@@ -774,29 +674,25 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 			var query2 = new QueryBuilder(QueryType.UPDATE, "categories");
 			query2.updateValuePair("categorieID", newID, true);
 			query2.addEqualsCondition("categorieID", catID, true, true);
-			executeSQL(query2.build());
-			query2.print();
+			m_db.simple_query(query2.build());
 
 			var query3 = new QueryBuilder(QueryType.UPDATE, "feeds");
 			query3.updateValuePair("category_id", "replace(category_id, '%s', '%s')".printf(catID, newID));
 			query3.addCustomCondition("instr(category_id, '%s')".printf(catID));
-			executeSQL(query3.build());
-			query3.print();
+			m_db.simple_query(query3.build());
 
 			var query = new QueryBuilder(QueryType.UPDATE, "categories");
 			query.updateValuePair("title", newName, true);
 			query.addEqualsCondition("categorieID", newID, true, true);
-			executeSQL(query.build());
+			m_db.simple_query(query.build());
 		}
 		else
 		{
 			var query = new QueryBuilder(QueryType.UPDATE, "categories");
 			query.updateValuePair("title", newName, true);
 			query.addEqualsCondition("categorieID", catID, true, true);
-			executeSQL(query.build());
+			m_db.simple_query(query.build());
 		}
-
-
 	}
 
 	public void move_category(string catID, string newParentID)
@@ -806,7 +702,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.updateValuePair("Parent", newParentID);
 		query.updateValuePair("Level", "%i".printf(parent.getLevel()+1));
 		query.addEqualsCondition("categorieID", catID);
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 	}
 
 	public void rename_feed(string feedID, string newName)
@@ -814,7 +710,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		var query = new QueryBuilder(QueryType.UPDATE, "feeds");
 		query.updateValuePair("name", newName, true);
 		query.addEqualsCondition("feed_id", feedID, true, true);
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 	}
 
 	public void move_feed(string feedID, string currentCatID, string? newCatID = null)
@@ -831,7 +727,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		var query = new QueryBuilder(QueryType.UPDATE, "feeds");
 		query.updateValuePair("category_id", catString, true);
 		query.addEqualsCondition("feed_id", feedID, true, true);
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 	}
 
 	public void removeCatFromFeed(string feedID, string catID)
@@ -840,18 +736,18 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		var query = new QueryBuilder(QueryType.UPDATE, "feeds");
 		query.updateValuePair("category_id", feed.getCatString().replace(catID + ",", ""), true);
 		query.addEqualsCondition("feed_id", feedID, true, true);
-		executeSQL(query.build());
+		m_db.simple_query(query.build());
 	}
 
 	public void delete_feed(string feedID)
 	{
-		executeSQL("DELETE FROM feeds WHERE feed_id = \"%s\"".printf(feedID));
+		m_db.simple_query("DELETE FROM feeds WHERE feed_id = \"%s\"".printf(feedID));
 		delete_articles(feedID);
 	}
 
 	public void addCachedAction(CachedActions action, string id, string? argument = "")
 	{
-		executeSQL("BEGIN TRANSACTION");
+		m_db.simple_query("BEGIN TRANSACTION");
 
 		var query = new QueryBuilder(QueryType.INSERT_OR_IGNORE, "main.CachedActions");
 		query.insertValuePair("action", "$ACTION");
@@ -859,14 +755,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.insertValuePair("argument", "$ARGUMENT");
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2 (query.get(), query.get().length, out stmt);
-		if (ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error("addCachedAction: " + sqlite_db.errmsg());
-		}
-
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		int action_position = stmt.bind_parameter_index("$ACTION");
 		int id_position = stmt.bind_parameter_index("$ID");
@@ -882,7 +771,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		while (stmt.step () == Sqlite.ROW) {}
 		stmt.reset ();
 
-		executeSQL("COMMIT TRANSACTION");
+		m_db.simple_query("COMMIT TRANSACTION");
 	}
 
 
@@ -893,15 +782,8 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		var query = new QueryBuilder(QueryType.SELECT, "CachedActions");
 		query.selectField("*");
 		query.build();
-		query.print();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error(query.get());
-			Logger.error("readCachedActions: " + sqlite_db.errmsg());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while(stmt.step () == Sqlite.ROW)
 		{
@@ -916,7 +798,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 	public void resetCachedActions()
 	{
 		Logger.warning("resetCachedActions");
-		executeSQL("DELETE FROM CachedActions");
+		m_db.simple_query("DELETE FROM CachedActions");
 	}
 
 	public bool cachedActionNecessary(CachedAction action)
@@ -928,13 +810,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.addEqualsCondition("action", "%i".printf(action.opposite()));
 		query.build();
 
-		Sqlite.Statement stmt;
-		int ec = sqlite_db.prepare_v2(query.get(), query.get().length, out stmt);
-		if(ec != Sqlite.OK)
-		{
-			Logger.error("cachedActionNecessary - %s".printf(sqlite_db.errmsg()));
-			Logger.error(query.get());
-		}
+		Sqlite.Statement stmt = m_db.prepare(query.get());
 
 		while(stmt.step () == Sqlite.ROW)
 		{
@@ -951,8 +827,7 @@ public class FeedReader.DataBase : DataBaseReadOnly {
 		query.addEqualsCondition("argument", action.getArgument(), true, true);
 		query.addEqualsCondition("id", action.getID(), true, true);
 		query.addEqualsCondition("action", "%i".printf(action.opposite()));
-		executeSQL(query.build());
-		query.print();
+		m_db.simple_query(query.build());
 	}
 
 }
diff --git a/src/SQLite.vala b/src/SQLite.vala
new file mode 100644
index 00000000..2652a056
--- /dev/null
+++ b/src/SQLite.vala
@@ -0,0 +1,153 @@
+//	This file is part of FeedReader.
+//
+//	FeedReader 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.
+//
+//	FeedReader 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 FeedReader.  If not, see <http://www.gnu.org/licenses/>.
+
+public errordomain SQLiteError
+{
+	FAIL
+}
+
+/* A wrapper around the low-level SQLite API */
+public class SQLite : GLib.Object {
+	private Sqlite.Database m_db;
+
+	public SQLite(string db_path, int busy_timeout = 1000)
+	{
+		var path = GLib.File.new_for_path(db_path);
+		var parent = path.get_parent();
+		if(!parent.query_exists())
+		{
+			try
+			{
+				parent.make_directory_with_parents();
+			}
+			catch(IOError.EXISTS e)
+			{
+			}
+		}
+
+		int rc = Sqlite.Database.open_v2(db_path, out m_db);
+		if(rc != Sqlite.OK)
+			throw new SQLiteError.FAIL("Can't open database: %d: %s".printf(m_db.errcode(), m_db.errmsg()));
+
+		m_db.busy_timeout(busy_timeout);
+	}
+
+	// Backwards compatibility interface
+	public Sqlite.Statement prepare(string query)
+	{
+		Sqlite.Statement stmt;
+		int rc = m_db.prepare_v2(query, query.length, out stmt);
+		if(rc != Sqlite.OK)
+			throw new SQLiteError.FAIL("Can't prepare statement: %d: %s\nSQL is %s".printf(m_db.errcode(), m_db.errmsg(), query));
+		return stmt;
+	}
+
+	public string errmsg()
+	{
+		return m_db.errmsg();
+	}
+
+	public void checkpoint()
+	{
+		m_db.wal_checkpoint("");
+	}
+
+	public void simple_query(string query)
+	{
+		string errmsg;
+		int ec = m_db.exec(query, null, out errmsg);
+		if (ec != Sqlite.OK)
+		{
+			throw new SQLiteError.FAIL("Failed to execute simple query: %d: %s\nSQL is: %s".printf(ec, errmsg, query));
+		}
+	}
+
+	public Gee.List<Gee.List<Value?>> execute(string query, ...)
+	{
+		var l = va_list();
+		Gee.List<string?> params = null;
+		while(true)
+		{
+			string? param = l.arg();
+			if(param == null)
+				break;
+			if(params == null)
+				params = new Gee.ArrayList<string?>();
+			params.add(param);
+		}
+		return executev(query, params);
+	}
+
+	public Gee.List<Gee.List<Value?>> executev(string query, Gee.List<string?>? params = null)
+	{
+		Sqlite.Statement stmt;
+		int rc = m_db.prepare_v2(query, query.length, out stmt);
+		if (rc != Sqlite.OK)
+		{
+			throw new SQLiteError.FAIL("Can't prepare statement: %d: %s\nSQL is: %s".printf(m_db.errcode(), m_db.errmsg(), query));
+		}
+
+		if(params != null)
+		{
+			for(int i = 1; i < params.size; ++i)
+			{
+				var param = params[i];
+				if(param == null)
+					stmt.bind_null(i);
+				else
+					stmt.bind_text(i, param);
+			}
+		}
+
+		var rows = new Gee.ArrayList<Gee.List<Value?>>();
+		while(stmt.step() == Sqlite.ROW)
+		{
+			var row = new Gee.ArrayList<Value?>();
+			for(int i = 0; i < stmt.column_count(); ++i)
+			{
+				Value? value;
+				switch(stmt.column_type(i))
+				{
+				case Sqlite.INTEGER:
+					value = Value(typeof(int));
+					value.set_int(stmt.column_int(i));
+					break;
+				case Sqlite.FLOAT:
+					value = Value(typeof(double));
+					value.set_double(stmt.column_double(i));
+					break;
+				case Sqlite.BLOB:
+					value = Value(typeof(void*));
+					value.set_pointer(stmt.column_blob(i));
+					break;
+				case Sqlite.NULL:
+					value = null;
+					break;
+				case Sqlite.TEXT:
+					value = Value(typeof(string));
+					value.take_string(stmt.column_text(i));
+					break;
+				default:
+					throw new SQLiteError.FAIL("Unknown column return type: %d".printf(stmt.column_type(i)));
+				}
+				row.add(value);
+			}
+			rows.add(row);
+		}
+		stmt.reset ();
+
+		return rows;
+	}
+}