- get SQL Developer (free) from Oracle
- I needed was a list of the system tables in Oracle which I found here.
- Next log in as the user who's schema you want to print.
- The basic query you want is:
FROM USER_TABLES t, USER_TAB_COLUMNS c
where t.TABLE_NAME = c.table_name;
- run the script using F5 and select the Script Output tab
- Save the output
You can repeat this process for other schemas and use a diff tool like beyond compare to find the differences.