PATTERN_ID

返回匹配模式实例的全分区唯一标识符整数值。

语法

PATTERN_ID()

注意

模式匹配函数必须用在 MATCH 子句 语法中；例如，如果单独调用 PATTERN_ID()，Vertica 将返回以下错误消息：

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

示例

以下语句分析了用户在 website2.com 的浏览历史并标识了用户从另一网站（进入）登录 website2.com 以及在做出购买之前（购买）浏览任意数量的其他页面（站内）的模式。查询也输出了 PATTERN_ID() 的值，表示匹配模式实例的全分区标识符。

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)

另请参阅