A Relational Table with Object Types
You can create a user-defined datatype and then use the new datatype in a relational table.
The data actually resides as column values in the table, rather than the column value being a pointer (REF
) to the data.
This methodology creates a column object or nested object that
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- Does not have an object identifier.
- Cannot be referenced using the
REF
operator.
SQL> CREATE TYPE address_typ AS OBJECT (
2 address1 VARCHAR2(32),
3 address2 VARCHAR2(32),
4 city VARCHAR2(16),
5 state CHAR(2),
6 zip CHAR(5) );
Type created.
SQL> CREATE TABLE customer (
2 id INTEGER PRIMARY KEY,
3 cust_address address_typ );
Table created.
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The address_typ
type is used as the datatype for the cust_address
column of a customer
relational table.
When object types are instantiated in this way, you create a column object or nested object.
If the user-defined type is in another schema, you must use the schema name as a qualifier of the datatype.
For example, if user scott
owns scotts_typ
object, use:
CREATE TABLE my_table( x scott.scotts_typ );
Actions speak louder than words.
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