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oracle-databasecountspatialvarray

How to count the number of elements in all Oracle varrays from table?


I have a table like this:

CREATE TABLE spatial_data (
  id NUMBER PRIMARY KEY,
  geometry SDO_GEOMETRY);

SDO_GEOMETRY has a field sdo_ordinates with the following type:

TYPE SDO_ORDINATE_ARRAY AS VARRAY(1048576) OF NUMBER

I can get the number of points for specified object:

select count(*)
from table(
    select s.geometry.sdo_ordinates
    from spatial_data s
    where s.id = 12345
);

How can I get count for several objects? It's not possible to use

where s.id in (1, 2, 3, 4, 5)

And I really care about performance. Maybe PL/SQL would be the right choice?


Solution

  • I think that you can do it with one query:

    select s.id, count(*)
      from spatial_data s, table(s.geometry.sdo_ordinates)
     group by s.id
    

    or you can write a plsql simple function that returns the count attribute of the SDO_ORDINATE_ARRAY VARRAY:

    create or replace function get_count(ar in SDO_ORDINATE_ARRAY) return number is
    begin
       return ar.count;
    end get_count;
    

    or even nicer add a member function to SDO_GEOMETRY TYPE which return the count attribute