The ALL_CONS_COLUMNS view provides information about the columns specified in constraints placed on tables accessible by the current user.

ownerTEXTUser name of the constraint’s owner.
schema_nameTEXTName of the schema in which the constraint belongs.
constraint_nameTEXTThe name of the constraint.
table_nameTEXTThe name of the table to which the constraint belongs.
column_nameTEXTThe name of the column referenced in the constraint.
positionSMALLINTThe position of the column within the object definition.
constraint_defTEXTThe definition of the constraint.