Known issues in Greenplum database related to Query Planner
Post date: Jan 25, 2014 3:49:39 PM
1. Issue 20453
For SQL queries of either of the following forms:
SELECT columns FROM table WHERE table.column NOT IN subquery;
SELECT columns FROM table WHERE table.column = ALL subquery;
tuples that satisfy both of the following conditions are not included in the result set:
a) table.column is NULL.
b) subquery returns the empty result.
2. Issue 21724
Greenplum Database executes an SQL query in two stages if a scalar subquery is involved. The output of the first stage plan is fed into the second stage plan as a external parameter. If the first stage plan generates zero tuples and directly contributes to the output of the second stage plan, incorrect results might be returned.