[DERBY-6013] Assert failure with ORDER BY in UNION used in sub-query

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 10.6.1.0, 10.6.2.1, 10.7.1.1, 10.8.1.2, 10.8.2.2, 10.8.3.0, 10.9.1.0, 10.10.1.1
• Component/s: SQL
• Labels: derby_triage10_11
• Urgency: Normal
• Issue & fix info: Repro attached
• Assignee: Unassigned
• Reporter: Knut Anders Hatlen
• Created: 13/Dec/12 17:01
• Updated: 19/Jun/13 10:14

Description

I see an assert failure when executing this sequence of statements using a debug version of 10.9.1.0 or trunk:

ij version 10.9
ij> connect 'jdbc:derby:memory:db;create=true';
ij> create table t(x int);
0 rows inserted/updated/deleted
ij> create table u(x int);
0 rows inserted/updated/deleted
ij> insert into t values 1,2,3,4,5;
5 rows inserted/updated/deleted
ij> insert into u values 4,5,6,7;
4 rows inserted/updated/deleted
ij> select * from sysibm.sysdummy1 where exists ((select * from t) union (select * from u where x = 4) order by x);
ERROR XJ001: Java exception: 'ASSERT FAILED getMatchingColumn() not expected to be called for tableConstructor: false
all: false
nestedInParens: false
correlation Name: null
null
tableNumber 3
level 1
resultSetNumber: 0
referencedTableMap: null
statementResultSet: false
: org.apache.derby.shared.common.sanity.AssertFailure'.

Using a non-debug build makes it fail more gracefully:

ij> select * from sysibm.sysdummy1 where exists ((select * from t) union (select * from u where x = 4) order by x);
ERROR 42X04: Column 'X' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE statement then 'X' is not a column in the target table.

However, I think the error message is misleading, as X is a valid column in the query. Seen for example by executing the nested query as a top-level query:

ij> (select * from t) union all (select * from u where x = 4) order by x;
X
-----------
1
2
3
4
4
5

6 rows selected

However, possibly related, if I simply add parentheses around the working query, it again fails with a complaint about the column X:

ij> ((select * from t) union all (select * from u where x = 4) order by x);
ERROR 42X78: Column 'X' is not in the result of the query expression.