Oracle all foreign key references

Question

I've inherited a schema so don't have complete knowledge/confidence in what is there.

I have a project table with a projectId. There are a whole bunch of other tables that reference this table by project id. What I want to do is run a query to establish:

1. Which tables have foreign key references to the project table on the project id
2. Which tables have a column called project id (in case foreign keys are not set up).

If it was SQL Server I know how to query the metadata but how do I do this in Oracle?

Answer 1

1)

select table_name
  from all_constraints
 where r_constraint_name = [your pk/uk constraint on PROJECTS(id)]

2)

select table_name
  from all_tab_columns
 where column_name = 'PROJECT_ID'

You may want to add an extra predicate containing the OWNER column.

Regards, Rob.

Answer 2

Ok. Here a request that give you the referenced table and column :

SELECT
 c_list.CONSTRAINT_NAME as NAME,
 substr(c_src.COLUMN_NAME, 1, 20) as SRC_COLUMN,
 c_dest.TABLE_NAME as DEST_TABLE,
 substr(c_dest.COLUMN_NAME, 1, 20) as DEST_COLUMN
FROM ALL_CONSTRAINTS c_list, ALL_CONS_COLUMNS c_src, ALL_CONS_COLUMNS c_dest
WHERE c_list.CONSTRAINT_NAME   = c_src.CONSTRAINT_NAME
 AND  c_list.OWNER             = c_src.OWNER
 AND  c_list.R_CONSTRAINT_NAME = c_dest.CONSTRAINT_NAME
 AND  c_list.OWNER             = c_dest.OWNER
 AND  c_list.CONSTRAINT_TYPE = 'R'
 AND  c_src.OWNER      = '<your-schema-here>'
 AND  c_src.TABLE_NAME = '<your-table-here>'
GROUP BY c_list.CONSTRAINT_NAME, c_src.TABLE_NAME,
    c_src.COLUMN_NAME, c_dest.TABLE_NAME, c_dest.COLUMN_NAME;

Which give you something like this:

NAME                  |SRC_COLUMN      |DEST_TABLE            | DEST_COLUMN
----------------------|----------------|----------------------|-----------
CFK_RUB_FOR           |FOR_URN         |T03_FORMAT            |FOR_URN
CFK_RUB_RUB           |RUB_RUB_URN     |T01_RUBRIQUE          |RUB_URN
CFK_RUB_SUP           |SUP_URN         |T01_SUPPORT           |SUP_URN
CFK_RUB_PRD           |PRD_URN         |T05_PRODUIT           |PRD_URN

You can forget the substr() function if the result is usable without. This is not my case.

Answer 3

1): SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_NAME='R' and R_CONSTRAINT_NAME='xxx'

where xxx is the name of the primary key constraint on the project table

2): SELECT * FROM USER_TAB_COLUMNS WHERE COLUMN_NAME='PROJECT_ID'