HIVE-28033: Fix TestMapJoinOperator to run on Tez

[Indhumathi27]

What changes were proposed in this pull request?

The configuration for HIVE_DEFAULT_NULLS_LAST is set to false when Tez is used. The change ensures compatibility with Tez and proper null handling during serialization.

Why are the changes needed?

With MapReduce (MR), SERIALIZATION_NULL_SORT_ORDER is not set, hence the default null sorting is NULL FIRST. For Tez, the null sorting needed to be adjusted to prevent EOFException and ensure correct test execution with the generated data.

Does this PR introduce any user-facing change?

No

Is the change a dependency upgrade?

No

How was this patch tested?

Test case

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Aggarwal-Raghav]

LGTM +1 (non-binding)

[difin]

LGTM, +1

[Indhumathi27]

@difin can you merge if the PR is okay

[Indhumathi27]

@okumin Can you help with review and merging this PR

[okumin]

I confirmed this part is applied only to Tez and that's why.

hive/ql/src/java/org/apache/hadoop/hive/ql/plan/PlanUtils.java

Lines 524 to 534 in eaa8189

	if (HiveConf.getVar(conf, ConfVars.HIVE_EXECUTION_ENGINE).equals("tez")) {
	// In tez we use a different way of transmitting the hash table.
	// We basically use ReduceSinkOperators and set the transfer to
	// be broadcast (instead of partitioned). As a consequence we use
	// a different SerDe than in the MR mapjoin case.
	StringBuilder order = new StringBuilder();
	StringBuilder nullOrder = new StringBuilder();
	for (FieldSchema f: fieldSchemas) {
	order.append("+");
	nullOrder.append(NullOrdering.defaultNullOrder(conf).getSign());
	}

[okumin]

+1

[Indhumathi27]

Thanks @okumin @Aggarwal-Raghav @difin for the review