diff --git a/lib/db.py b/lib/db.py
index a6bca83..324251e 100644
--- a/lib/db.py
+++ b/lib/db.py
@@ -46,7 +46,8 @@ class DB:
     def create_tables(self):
         """Create the tables if not existing - assumes connected"""
 
-        commands = (
+        schemes = dict()
+        schemes[1] = (
             """
         CREATE TABLE scheme (
             id SERIAL PRIMARY KEY,
@@ -54,7 +55,7 @@ class DB:
             )
             """,
             "INSERT INTO scheme (version) VALUES(1)",
-            """ DROP TABLE IF EXISTS revisions""",
+            """DROP TABLE IF EXISTS revisions """,
             """ CREATE TABLE revisions (
                 id                  SERIAL PRIMARY KEY,
                 project             VARCHAR(255) NOT NULL,
@@ -71,14 +72,32 @@ class DB:
             CREATE UNIQUE INDEX ppr ON revisions (project, package, rev);
             """,
         )
+        schemes[2] = (
+            """DROP TABLE IF EXISTS links""",
+            """
+            CREATE TABLE links (
+                id            SERIAL PRIMARY KEY,
+                revision_id   INTEGER,
+                project       VARCHAR(255) NOT NULL,
+                package       VARCHAR(255) NOT NULL
+            )
+            """,
+            """
+            UPDATE scheme SET version=2 
+            """,
+        )
 
-        if self.schema_version() > 0:
+        schema_version = self.schema_version()
+        if (schema_version + 1) not in schemes:
             return
         try:
             cur = self.conn.cursor()
             # create table one by one
-            for command in commands:
-                cur.execute(command)
+            for version, commands in schemes.items():
+                if version <= schema_version:
+                    continue
+                for command in commands:
+                    cur.execute(command)
             # close communication with the PostgreSQL database server
             cur.close()
             # commit the changes
diff --git a/lib/db_revision.py b/lib/db_revision.py
index 02109d6..7fe99c8 100644
--- a/lib/db_revision.py
+++ b/lib/db_revision.py
@@ -14,8 +14,12 @@ class DBRevision:
         ) = row
 
     def links_to(self, db, project, package):
-        pass
-    
+        db.cursor().execute(
+            "INSERT INTO links (revision_id, project, package) VALUES (%s,%s,%s)",
+            (self.dbid, project, package),
+        )
+        print("links_to", project, package)
+
     @classmethod
     def import_obs_rev(cls, db, revision):
         cur = db.cursor()
@@ -41,7 +45,7 @@ class DBRevision:
         cur = db.cursor()
         cur.execute(
             "SELECT * FROM revisions where project=%s and package=%s and rev=%s",
-            (project, package, rev),
+            (project, package, str(rev)),
         )
         row = cur.fetchone()
         cur.close()