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https://issues.apache.org/jira/browse/HIVE-25758?focusedWorklogId=761845&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-761845
]
ASF GitHub Bot logged work on HIVE-25758:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 25/Apr/22 15:16
Start Date: 25/Apr/22 15:16
Worklog Time Spent: 10m
Work Description: zabetak commented on code in PR #2966:
URL: https://github.com/apache/hive/pull/2966#discussion_r857739177
##########
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/HiveCalciteUtil.java:
##########
@@ -1257,15 +1249,26 @@ public Void visitCall(RexCall call) {
}
public boolean hasDisjunction(RexNode node) {
- // clear the state
- inNegation = false;
- hasDisjunction = false;
-
node.accept(this);
return hasDisjunction;
}
}
+ /**
+ * Find disjunction (OR) in an expression (at any level of nesting).
Review Comment:
`Find` implies that we are going to return a disjunctive expression.
Suggestion:
`Returns whether the expression has disjunctions (OR) at any level of
nesting.`
##########
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/HiveCalciteUtil.java:
##########
@@ -1257,15 +1249,26 @@ public Void visitCall(RexCall call) {
}
public boolean hasDisjunction(RexNode node) {
- // clear the state
- inNegation = false;
- hasDisjunction = false;
-
node.accept(this);
return hasDisjunction;
}
}
+ /**
+ * Find disjunction (OR) in an expression (at any level of nesting).
+ *
+ * Example 1: OR(=($0, $1), IS NOT NULL($2))):INTEGER (OR in the top-level
expression)
+ * Example 2: NOT(AND(=($0, $1), IS NOT NULL($2))
+ * this is equivalent to OR((<>($0, $1), IS NULL($2))
+ * Example 3: AND(OR(=($0, $1), IS NOT NULL($2)))) (OR in inner expression)
+ *
+ * @param node the expression where to look for disjunctions.
+ * @return true if the given expressions contains a disjunction, false
otherwise.
+ */
+ public static boolean hasDisjuction(RexNode node) {
+ return new DisjunctivePredicatesFinder().hasDisjunction(node);
Review Comment:
nit to get rid of the `DisjunctivePredicateFinder#hasDisjunction` method:
```
DisjunctivePredicateFinder finder = new DisjunctivePredicateFinder();
node.accept(finder);
return finder.hasDisjunction;
```
##########
ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/HiveCalciteUtil.java:
##########
@@ -1214,6 +1214,58 @@ public FixNullabilityShuttle(RexBuilder rexBuilder,
}
}
+ /**
+ * Find disjunction (OR) in an expression (at any level of nesting).
+ *
+ * Example 1: OR(=($0, $1), IS NOT NULL($2))):INTEGER (OR in the top-level
expression)
+ * Example 2: NOT(AND(=($0, $1), IS NOT NULL($2))
+ * this is equivalent to OR((<>($0, $1), IS NULL($2))
+ * Example 3: AND(OR(=($0, $1), IS NOT NULL($2)))) (OR in inner expression)
+ */
Review Comment:
I had in mind compiling with `-Pjavadoc` profile and checking for new errors
in this class. Actually I am afraid of `<>` symbols as well as `$`. Don't
remember if it is fine to use them like that.
Issue Time Tracking
-------------------
Worklog Id: (was: 761845)
Time Spent: 3h 20m (was: 3h 10m)
> OOM due to recursive application of CBO rules
> ---------------------------------------------
>
> Key: HIVE-25758
> URL: https://issues.apache.org/jira/browse/HIVE-25758
> Project: Hive
> Issue Type: Bug
> Components: CBO, Query Planning
> Affects Versions: 4.0.0
> Reporter: Alessandro Solimando
> Assignee: Alessandro Solimando
> Priority: Major
> Labels: pull-request-available
> Time Spent: 3h 20m
> Remaining Estimate: 0h
>
>
> Reproducing query is as follows:
> {code:java}
> create table test1 (act_nbr string);
> create table test2 (month int);
> create table test3 (mth int, con_usd double);
> EXPLAIN
> SELECT c.month,
> d.con_usd
> FROM
> (SELECT
> cast(regexp_replace(substr(add_months(from_unixtime(unix_timestamp(),
> 'yyyy-MM-dd'), -1), 1, 7), '-', '') AS int) AS month
> FROM test1
> UNION ALL
> SELECT month
> FROM test2
> WHERE month = 202110) c
> JOIN test3 d ON c.month = d.mth; {code}
>
> Different plans are generated during the first CBO steps, last being:
> {noformat}
> 2021-12-01T08:28:08,598 DEBUG [a18191bb-3a2b-4193-9abf-4e37dd1996bb main]
> parse.CalcitePlanner: Plan after decorre
> lation:
> HiveProject(month=[$0], con_usd=[$2])
> HiveJoin(condition=[=($0, $1)], joinType=[inner], algorithm=[none],
> cost=[not available])
> HiveProject(month=[$0])
> HiveUnion(all=[true])
>
> HiveProject(month=[CAST(regexp_replace(substr(add_months(FROM_UNIXTIME(UNIX_TIMESTAMP,
> _UTF-16LE'yyyy-MM-d
> d':VARCHAR(2147483647) CHARACTER SET "UTF-16LE"), -1), 1, 7),
> _UTF-16LE'-':VARCHAR(2147483647) CHARACTER SET "UTF-
> 16LE", _UTF-16LE'':VARCHAR(2147483647) CHARACTER SET "UTF-16LE")):INTEGER])
> HiveTableScan(table=[[default, test1]], table:alias=[test1])
> HiveProject(month=[$0])
> HiveFilter(condition=[=($0, CAST(202110):INTEGER)])
> HiveTableScan(table=[[default, test2]], table:alias=[test2])
> HiveTableScan(table=[[default, test3]], table:alias=[d]){noformat}
>
> Then, the HEP planner will keep expanding the filter expression with
> redundant expressions, such as the following, where the identical CAST
> expression is present multiple times:
>
> {noformat}
> rel#118:HiveFilter.HIVE.[].any(input=HepRelVertex#39,condition=IN(CAST(regexp_replace(substr(add_months(FROM_UNIXTIME(UNIX_TIMESTAMP,
> _UTF-16LE'yyyy-MM-dd':VARCHAR(2147483647) CHARACTER SET "UTF-16LE"), -1), 1,
> 7), _UTF-16LE'-':VARCHAR(2147483647) CHARACTER SET "UTF-16LE",
> _UTF-16LE'':VARCHAR(2147483647) CHARACTER SET "UTF-16LE")):INTEGER,
> CAST(regexp_replace(substr(add_months(FROM_UNIXTIME(UNIX_TIMESTAMP,
> _UTF-16LE'yyyy-MM-dd':VARCHAR(2147483647) CHARACTER SET "UTF-16LE"), -1), 1,
> 7), _UTF-16LE'-':VARCHAR(2147483647) CHARACTER SET "UTF-16LE",
> _UTF-16LE'':VARCHAR(2147483647) CHARACTER SET "UTF-16LE")):INTEGER,
> 202110)){noformat}
>
> The problem seems to come from a bad interaction of at least
> _HiveFilterProjectTransposeRule_ and
> {_}HiveJoinPushTransitivePredicatesRule{_}, possibly more.
> Most probably then UNION part can be removed and the reproducer be simplified
> even further.
>
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