Mohammad, How do you define a parent table and a child table? One could assume that this is defined by Referential Integrity constraints (in this case you should look at dba_constraints and work out the logic and read up on connect by to work out the sql). But in the absence of an example of data and desired output or a good requirements definition, we are left to guess and speculate. And it is not good to guess and speculate... Regards, Daniel Fink ------- Original Message ------- On 6/15/2010 3:26 PM Mohammad Seliem wrote: Could you please help me by providing a SQL that list schema tables in parent/child tree. Example: TableName Level TAB1 1 TAB2 2 TAB3 2 TAB4 3 Thanks, Mohamed Seliem -- //www.freelists.org/webpage/oracle-l