[CALCITE-1872] PREV is parsed as LAST when the name of the pattern referenced is not the same with the pattern being defined

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Fix Version/s: 1.14.0
• Labels: match
• Assignee: Zhiqiang He
• Reporter: Dian Fu
• Created: 05/Jul/17 08:29
• Updated: 05/Oct/17 20:51
• Resolved: 08/Jul/17 17:07

Description

For table Ticker:

symbol: string
tstamp: long
price: int

, the UP in the following sql

SELECT *
FROM Ticker
MATCH_RECOGNIZE (
  MEASURES
    STRT.tstamp AS start_tstamp,
    LAST(DOWN.tstamp) AS up_days,
    LAST(UP.tstamp) AS total_days
  PATTERN (STRT DOWN+ UP+)
  DEFINE
    DOWN AS DOWN.price < PREV(DOWN.price),
    UP AS UP.price > PREV(DOWN.price)
) AS T

is parsed as

">(PREV(UP.$2, 0), LAST(DOWN.$2, 1))"

I think this is not correct. PREV defines a physical offset, while LAST defines a logical offset.

Issue Links

• duplicates: CALCITE-1871 Nesting LAST within PREV is not parsed correctly for MATCH_RECOGNIZE