[
https://issues.apache.org/jira/browse/CALCITE-3021?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16849090#comment-16849090
]
Michael Mior commented on CALCITE-3021:
---------------------------------------
Fixed in
[{{ab40586}}|https://github.com/apache/calcite/commit/ab40586dd6b6a8daff5054176db463d63e9c250c]
> Equality of nested ROWs returns false for identical values
> ----------------------------------------------------------
>
> Key: CALCITE-3021
> URL: https://issues.apache.org/jira/browse/CALCITE-3021
> Project: Calcite
> Issue Type: Bug
> Affects Versions: 1.19.0
> Reporter: Ruben Quesada Lopez
> Assignee: Ruben Quesada Lopez
> Priority: Minor
> Labels: pull-request-available
> Fix For: 1.20.0
>
> Time Spent: 50m
> Remaining Estimate: 0h
>
> Problem can be reproduced via:
> {code:sql}
> select distinct * from (values
> (1, ROW(1,1)),
> (1, ROW(1,1)),
> (2, ROW(2,2))) as v(id,struct);
> {code}
> Which incorrectly returns a duplicated value:
> {code}
> +----+--------+
> | ID | STRUCT |
> +----+--------+
> | 1 | {1, 1} |
> | 1 | {1, 1} |
> | 2 | {2, 2} |
> +----+--------+
> (3 rows)
> {code}
> The root cause is that currently ArrayEqualityComparer (which is used as
> comparer for JavaRowFormat.ARRAY) performs the array comparison based on
> Arrays#equals and Arrays#hashCode (see Functions.java):
> {code:java}
> private static class ArrayEqualityComparer implements
> EqualityComparer<Object[]> {
> public boolean equal(Object[] v1, Object[] v2) {
> return Arrays.equals(v1, v2);
> }
> public int hashCode(Object[] t) {
> return Arrays.hashCode(t);
> }
> }
> {code}
> This will lead to incorrect comparisons in case of multidimensional arrays,
> e.g. a row (array) with a struct field (another array) inside. To fix the
> issue, Arrays#deepEquals / Arrays#deepHashCode should be used:
> {code:java}
> private static class ArrayEqualityComparer implements
> EqualityComparer<Object[]> {
> public boolean equal(Object[] v1, Object[] v2) {
> return Arrays.deepEquals(v1, v2);
> }
> public int hashCode(Object[] t) {
> return Arrays.deepHashCode(t);
> }
> }
> {code}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
