Throw when can't read database revision

ocdb.cpp

@@ -23,7 +23,10 @@ OCdb::OCdb(std::string db_file) {
 		!request("CREATE TABLE IF NOT EXISTS caches (code TEXT PRIMARY KEY, name TEXT, location TEXT, type TEXT, status TEXT, size TEXT, difficulty REAL, terrain REAL, country TEXT, region TEXT, owner TEXT);") || 
 		!request("CREATE TABLE IF NOT EXISTS logs (uuid TEXT PRIMARY KEY, cache_code TEXT, date TEXT, user TEXT, type TEXT);"))
 		throw 1;
-	read_revision();
+	if (!read_revision()) {
+		Debug(1) << "Error reading database revision, database may be corrupt or empty.\n";
+		throw 1;
+	}
 }
 
 OCdb::~OCdb() {