PATTERN_ID

Returns an integer value that is a partition-wide unique identifier for the instance of the pattern that matched.

Syntax

PATTERN_ID()

Notes

Pattern matching functions must be used in MATCH Clause syntax; for example, if call PATTERN_ID() on its own, Vertica returns the following error message:

=> SELECT pattern_id();
ERROR:  query with pattern matching function pattern_id must include a MATCH clause

Example

This example uses the schema defined in Event Series Pattern Matching in Analyzing Data. For a more detailed example, see that topic.

The following statement analyzes users' browsing history on website2.com and identifies patterns where the user landed on website2.com from another Web site (Entry) and browsed to any number of other pages (Onsite) before making a purchase (Purchase). The query also outputs values for PATTERN_ID(), which represents the partition-wide identifier for the instance of the pattern that matched.

SELECT uid,
       sid,
       ts,
       refurl,
       pageurl,
       action,
       pattern_id()
FROM clickstream_log
MATCH
  (PARTITION BY uid, sid ORDER BY ts
   DEFINE
     Entry    AS RefURL  NOT ILIKE '%website2.com%' AND PageURL ILIKE '%website2.com%',
     Onsite   AS PageURL ILIKE     '%website2.com%' AND Action='V',
     Purchase AS PageURL ILIKE     '%website2.com%' AND Action = 'P'
   PATTERN
     P AS (Entry Onsite* Purchase)
   ROWS MATCH FIRST EVENT); 


uid | sid |    ts    |        refurl        |       pageurl        | action | pattern_id
----+-----+----------+----------------------+----------------------+--------+------------
1   | 100 | 12:00:00 | website1.com         | website2.com/home    | V      |          1
1   | 100 | 12:01:00 | website2.com/home    | website2.com/floby   | V      |          1
1   | 100 | 12:02:00 | website2.com/floby   | website2.com/shamwow | V      |          1
1   | 100 | 12:03:00 | website2.com/shamwow | website2.com/buy     | P      |          1
2   | 100 | 12:10:00 | website1.com         | website2.com/home    | V      |          1
2   | 100 | 12:11:00 | website2.com/home    | website2.com/forks   | V      |          1
2   | 100 | 12:13:00 | website2.com/forks   | website2.com/buy     | P      |          1
(7 rows)

See Also