>My current user is SYSTEM.i gave all sql privileges to the user SYSTEM on table which i created.
How did you give those privileges? Via an hdbrole? If you create your schema and table via the repository (hdbschema and hdbtable/hdbdd), then even user SYSTEM doesn't have access to them initial. All the objects are created by and owned by _SYS_REPO - regardless of who created and activated the designtime objects. Therefore you must create a role and grant it to your user or grant access via special stored procedures.