diff --git a/expected/test_ddl_triggers.out b/expected/test_ddl_triggers.out
index 53fb677..14e4b04 100644
--- a/expected/test_ddl_triggers.out
+++ b/expected/test_ddl_triggers.out
@@ -67,6 +67,8 @@ NOTICE:  trigger "update_updated_at_trigger" for table "c.t4" does not exist, sk
 NOTICE:  trigger "test_quota" for table "c.t4" does not exist, skipping
 NOTICE:  trigger "test_quota_per_row" for table "c.t4" does not exist, skipping
 NOTICE:  Column cartodb_id already exists
+NOTICE:  Existing cartodb_id field does not have an associated sequence, renaming
+NOTICE:  Trying to recover data from _cartodb_id0 coumn
 NOTICE:  event trigger "cdb_on_relation_create" does not exist, skipping
 NOTICE:  event trigger "cdb_on_relation_drop" does not exist, skipping
 NOTICE:  event trigger "cdb_on_alter_column" does not exist, skipping
diff --git a/scripts-available/CDB_CartodbfyTable.sql b/scripts-available/CDB_CartodbfyTable.sql
index 8c02e1c..72cd4ad 100644
--- a/scripts-available/CDB_CartodbfyTable.sql
+++ b/scripts-available/CDB_CartodbfyTable.sql
@@ -89,13 +89,21 @@ BEGIN
 
     IF had_column THEN
 
+      SELECT pg_catalog.pg_get_serial_sequence(reloid::text, 'cartodb_id')
+        AS seq INTO rec2;
+
       -- Check data type is an integer
-      SELECT t.typname, t.oid, a.attnotnull FROM pg_type t, pg_attribute a
+      SELECT
+        pg_catalog.pg_get_serial_sequence(reloid::text, 'cartodb_id') as seq,
+        t.typname, t.oid, a.attnotnull FROM pg_type t, pg_attribute a
        WHERE a.atttypid = t.oid AND a.attrelid = reloid AND NOT a.attisdropped
          AND a.attname = 'cartodb_id'
       INTO STRICT rec;
-      IF rec.oid NOT IN (20,21,23) THEN -- int2, int4, int8 {
+      -- 20=int2, 21=int4, 23=int8
+      IF rec.oid NOT IN (20,21,23) THEN
         RAISE NOTICE 'Existing cartodb_id field is of invalid type % (need int2, int4 or int8), renaming', rec.typname;
+      ELSIF rec.seq IS NULL THEN
+        RAISE NOTICE 'Existing cartodb_id field does not have an associated sequence, renaming';
       ELSE -- }{
         sql := 'ALTER TABLE ' || reloid::text || ' ALTER COLUMN cartodb_id SET NOT NULL';
         IF NOT EXISTS ( SELECT c.conname FROM pg_constraint c, pg_attribute a
diff --git a/test/CDB_CartodbfyTableTest.sql b/test/CDB_CartodbfyTableTest.sql
index a467903..8102fc2 100644
--- a/test/CDB_CartodbfyTableTest.sql
+++ b/test/CDB_CartodbfyTableTest.sql
@@ -182,18 +182,24 @@ SELECT CDB_CartodbfyTableCheck('t', 'cartodbfied with view');
 DROP VIEW v;
 DROP TABLE t;
 
--- table with existing cartodb_id field ot type text
+-- table with existing cartodb_id field of type text
 CREATE TABLE t AS SELECT 10::text as cartodb_id;
 SELECT CDB_CartodbfyTableCheck('t', 'text cartodb_id');
 select cartodb_id/2 FROM t; 
 DROP TABLE t;
 
--- table with existing cartodb_id field ot type text not casting
+-- table with existing cartodb_id field of type text not casting
 CREATE TABLE t AS SELECT 'nan' as cartodb_id;
 SELECT CDB_CartodbfyTableCheck('t', 'uncasting text cartodb_id');
 select cartodb_id,_cartodb_id0 FROM t; 
 DROP TABLE t;
 
+-- table with existing cartodb_id field of type int4 not sequenced
+CREATE TABLE t AS SELECT 1::int4 as cartodb_id;
+SELECT CDB_CartodbfyTableCheck('t', 'unsequenced cartodb_id');
+select cartodb_id FROM t; 
+DROP TABLE t;
+
 -- TODO: table with existing custom-triggered the_geom
 
 DROP FUNCTION CDB_CartodbfyTableCheck(regclass, text);
diff --git a/test/CDB_CartodbfyTableTest_expect b/test/CDB_CartodbfyTableTest_expect
index bee3b23..4a3d2b0 100644
--- a/test/CDB_CartodbfyTableTest_expect
+++ b/test/CDB_CartodbfyTableTest_expect
@@ -40,5 +40,9 @@ SELECT 1
 uncasting text cartodb_id cartodbfied fine
 1|nan
 DROP TABLE
+SELECT 1
+unsequenced cartodb_id cartodbfied fine
+1
+DROP TABLE
 DROP FUNCTION
 DROP FUNCTION