insertion in a table of objects with nested table in oracle

User_5EVCZ

I have a problem inserting in a nested table in oracle

These are the relevant types and tables;

create type movies_type as Table of ref movie_type;

create type actor_type under person_type

(

starring movies_type

) Final;

create table actor of actor_type

NESTED TABLE starring STORE AS starring_nt;

this is how i tried to insert

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YY'),TO_DATE('27/12/2016', 'DD/MM/YY'),'USA', movies_type(select ref(m) from movie m where movie_id in (7, 8, 9))));

this doesn't work, it gives

SQL Error: ORA-00936: missing expression

which isn't very helpful.

i also tried nesting the select statement in parenthesis because i thought it might have been a syntax error

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YY'),TO_DATE('27/12/2016', 'DD/MM/YY'),'USA', movies_type((select ref(m) from movie m where movie_id in (7, 8, 9)))));

but it said

SQL ERROR ORA-01427: single-row subquery returns more than one row

so i changed it to this

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YY'),TO_DATE('27/12/2016', 'DD/MM/YY'),'USA', movies_type((select ref(m) from movie m where movie_id=7))));

which worked but it isn't what i want since it doesn't allow me to have multiple values in

movies_type

i don't understand what the problem is exactly and the errors messages aren't helpful

why does it say missing expression?

and why in the second case it gives single-row sub-query returns more than one row?

thank you very much.

Mike Kutz

movies_type() is the CONSTRUCTOR FUNCTION for movies_type

It requires 1 or more instances of movie_type. Each one separated by a comma.

You're only making a single instance in your SQL.

The magic incantation you seek is:

Cast(multiset( select... ) as movies_type)

How It Works

movies_type is a Nested Table type.

You can Construct an NT of cardinality 1 by specifying a single Scalar SQL statement. (this is what you have in your 3rd attempt)

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
   ,movies_type(
       (select ref(m) from movie m where movie_id = 7) -- single element
   )
));

Additionally, you can construct an NT of cardinality n by specifying n elements; each one separated by a comma. In this example, I supply 3x Scalar SQL statements.

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
   ,movies_type(
       (select ref(m) from movie m where movie_id = 7), -- element 1
       (select ref(m) from movie m where movie_id = 8), -- element 2
       (select ref(m) from movie m where movie_id = 9)  -- element 3
   )
));

But, that's not what you want.

In order to turn a SELECT statement into an Array of elements, you need to use cast(multiset() as data_type) like so:

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
   ,cast(multiset(
                   select ref(m) from movie m where movie_id in (7,8,9)
                ) as movies_type)
));

Mike Kutz

I'm going to continue answering your question on DBA StackExchange first.

additionally, this should be posted in SQL & PL/SQL.

I'll copy&paste the answer here afterwards.

Mike Kutz

Code Review Notes:

• Always use 4-digit years in string-date conversions (yyyy not yy )
• SQL Object (Type ) evolution is a PITA. This is why they aren't readily used as columns/tables
  • Try to add rating and runtime to movie_type without dropping/deleting anything.

setup SQL:

create type movie_type as Object
(
  MOVIE_ID NUMBER(15),
  TITLE VARCHAR(50) ,
  GENDER  VARCHAR(30), -- typo
  RELEASE_DATE DATE,
  RUNNING_TIME NUMBER,
  BUDGET NUMBER
) Final;
/

create table MOVIE of movie_type;

ALTER TABLE MOVIE
  ADD CONSTRAINT PK_MOVIE_ID PRIMARY KEY (MOVIE_ID);

ALTER TABLE MOVIE modify TITLE not null;

INSERT INTO MOVIE (MOVIE_ID, TITLE, GENDER, RELEASE_DATE, RUNNING_TIME, BUDGET) VALUES (7,'Star Wars','epic space opera',TO_DATE('25/05/1977', 'DD/MM/YY'),121,11000000);
INSERT INTO MOVIE (MOVIE_ID, TITLE, GENDER, RELEASE_DATE, RUNNING_TIME, BUDGET) VALUES (8,'The Empire Strikes Back','epic space opera',TO_DATE('17/05/1980', 'DD/MM/YY'),124,18000000);
INSERT INTO MOVIE (MOVIE_ID, TITLE, GENDER, RELEASE_DATE, RUNNING_TIME, BUDGET) VALUES (9,'Return of the Jedi','epic space opera',TO_DATE('25/05/1983', 'DD/MM/YY'),132,32500000);
commit;

create type movies_type as Table of ref movie_type;
/

create type person_type as object
(
    person_id   int,
    first_name  varchar2(50 char),
    last_name   varchar2(50 char),
    dob         date,
    dod         date,
    country     varchar2(50 char)
) not final;
/

create type actor_type under person_type
(
    starring movies_type
) Final;
/

create table actor of actor_type
NESTED TABLE starring STORE AS starring_nt;

Tear down SQL:

drop table movie;
drop table actor;
drop type actor_type;drop type movies_type;
drop type movie_type;
drop type person_type;

Mike Kutz

movies_type() is the CONSTRUCTOR FUNCTION for movies_type

It requires 1 or more instances of movie_type. Each one separated by a comma.

You're only making a single instance in your SQL.

The magic incantation you seek is:

Cast(multiset( select... ) as movies_type)

How It Works

movies_type is a Nested Table type.

You can Construct an NT of cardinality 1 by specifying a single Scalar SQL statement. (this is what you have in your 3rd attempt)

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
   ,movies_type(
       (select ref(m) from movie m where movie_id = 7) -- single element
   )
));

Additionally, you can construct an NT of cardinality n by specifying n elements; each one separated by a comma. In this example, I supply 3x Scalar SQL statements.

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
   ,movies_type(
       (select ref(m) from movie m where movie_id = 7), -- element 1
       (select ref(m) from movie m where movie_id = 8), -- element 2
       (select ref(m) from movie m where movie_id = 9)  -- element 3
   )
));

But, that's not what you want.

In order to turn a SELECT statement into an Array of elements, you need to use cast(multiset() as data_type) like so:

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
   ,cast(multiset(
                   select ref(m) from movie m where movie_id in (7,8,9)
                ) as movies_type)
));

odie_63

As an alternative to cast(multiset() as movies_type) :

insert into actor values(
actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA', (
  select cast(collect(ref(m)) as movies_type) from movie m where movie_id in (7,8,9)
) 
));

Or, using MOVIE primary key as OID and scoped REFs :

create table MOVIE of movie_type (MOVIE_ID primary key) 
object identifier is primary key;

alter table starring_nt add (scope for (column_value) is movie);

we may construct REFs via MAKE_REF :

insert into actor values
(actor_type(29,'Carrie','Fisher',TO_DATE('21/10/1956', 'DD/MM/YYYY'),TO_DATE('27/12/2016', 'DD/MM/YYYY'),'USA'
  , movies_type(
    make_ref(movie,7)
   , make_ref(movie,8)
   , make_ref(movie,9)
   ) 
));