ORCA: fallback the locking clause

If the current GDD is closed and there is a `forupdate` statement,
ORCA and planner does not need to generate a `LockRows` operator,
expect the table is foreign table. However, if the current GDD is
enabled, ORCA will generate a plan without the `LockRows` operator,
which is a wrong plan.

Supporting locking clauses in ORCA is a very difficult thing. Because
ORCA does not fill `root->glob->paramExecTypes` in every operator,
even if ORCA generates the `LockRows` operator, it may not working
in the executor. For details, please refer to the EPQ(evalPlanQual)
mechanism.

Also I don't think ORCA should consider supporting locking clause.
ORCA is an optimizer that is more biased towards OLAP scenarios.
Support the EPQ mechanism will make ORCA more complex and more
difficult to expand.

Author: jiaqizho

contrib/pax_storage/src/test/isolation2/sql/gdd/concurrent_update.sql

@@ -177,9 +177,7 @@ DROP TABLE t_concurrent_update;
 1: update t_splitupdate_raise_error set a = a + 1;
 
 2: begin;
--- TODO: turn off orca, we should fix this until ORCA
--- can generate lockrows plannode.
-2: set optimizer = off;
+-- ORCA will fallback
 2&: select * from t_splitupdate_raise_error for update;
 
 1: end;

src/backend/gpopt/translate/CTranslatorDXLToPlStmt.cpp

@@ -4723,14 +4723,7 @@ CTranslatorDXLToPlStmt::TranslateDXLDml(
 		isSplit = true; // AO tables are always use split updates
 	}
 
-	if (md_rel->IsPartitioned())
-	{
-		dml->forceTupleRouting = true;
-	}
-	else
-	{
-		dml->forceTupleRouting = false;
-	}
+	dml->forceTupleRouting = md_rel->IsPartitioned();
 
 	if (IMDRelation::EreldistrMasterOnly != md_rel->GetRelDistribution())
 	{

src/backend/gpopt/translate/CTranslatorQueryToDXL.cpp

@@ -627,6 +627,12 @@ CTranslatorQueryToDXL::TranslateSelectQueryToDXL()
 		}
 	}
 
+	// Locking clause is not supported.
+	if (m_query->canOptSelectLockingClause) {
+		GPOS_RAISE(gpdxl::ExmaDXL, gpdxl::ExmiQuery2DXLUnsupportedFeature,
+			GPOS_WSZ_LIT("Locking clause"));
+	}
+
 	// RETURNING is not supported yet.
 	if (m_query->returningList)
 	{

src/test/isolation2/expected/gdd/concurrent_update.out

@@ -402,10 +402,7 @@ UPDATE 1
 
 2: begin;
 BEGIN
--- TODO: turn off orca, we should fix this until ORCA
--- can generate lockrows plannode.
-2: set optimizer = off;
-SET
+-- ORCA will fallback
 2&: select * from t_splitupdate_raise_error for update;  <waiting ...>
 
 1: end;

src/test/isolation2/expected/gdd/concurrent_update_optimizer.out

@@ -402,10 +402,7 @@ UPDATE 1
 
 2: begin;
 BEGIN
--- TODO: turn off orca, we should fix this until ORCA
--- can generate lockrows plannode.
-2: set optimizer = off;
-SET
+-- ORCA will fallback
 2&: select * from t_splitupdate_raise_error for update;  <waiting ...>
 
 1: end;