Relational Database

[klng]

I have a system installed on Sun solaris platform.
wanted to do some reverse engineering..
does anyone know that by any chance i can retrieve the Entity Relationship between tables from the database itself?

[dknight]

You can download Oracle Designer from Technet and try.

The reverse engineering functionality may not come with the trial copy.

If you have an Enterprise license, you might have a CD with Designer floating around your workplace. Otherwise, you might be able to get a free copy with your license from Oracle.

Good luck.

[kmesser]

select
b.constraint_name "CHILD CONSTRAINT", e.constraint_name "PARENT CONSTRAINT",
b.table_name "CHILD TABLE", e.table_name "PARENT TABLE",
b.column_name "CHILD COLUMN", e.column_name "PARENT COLUMN",
c.data_type "CHILD DATATYPE", f.data_type "PARENT DATATYPE",
c.data_length "CHILD DATA LENGTH", f.data_length "PARENT DATA LENGTH",
c.data_precision "CHILD PRECISION", f.data_precision "PARENT PRECISION",
c.data_scale "CHILD SCALE", f.data_scale "PARENT SCALE"
from
dba_constraints a,
dba_cons_columns b,
dba_tab_columns c,
dba_constraints d,
dba_cons_columns e,
dba_tab_columns f
where
a.constraint_name= b.constraint_name
and a.constraint_type = 'R'
and b.column_name = c.column_name
and b.table_name = c.table_name
and b.owner = '&&owner'
and d.constraint_name= e.constraint_name
and d.constraint_name = a.r_constraint_name
and e.column_name = f.column_name
and e.table_name = f.table_name
and e.owner = '&&owner'
/


This query will take a few minutes, and eats resources, so try it first somewhere besides production if you can . . .