CARDINALITY

Syntax

Description of the illustration cardinality.gif

Purpose

CARDINALITY returns the number of elements in a nested table. The return type is NUMBER. If the nested table is empty, or is a null collection, then CARDINALITY returns NULL.

Examples

The following example shows the number of elements in the nested table column ad_textdocs_ntab of the sample table pm.print_media:

SELECT product_id, CARDINALITY(ad_textdocs_ntab)
   FROM print_media;

PRODUCT_ID CARDINALITY(AD_TEXTDOCS_NTAB)
---------- -----------------------------
      3060                             3
      2056                             3
      3106                             3
      2268                             3