From 1f4ba2f255139439612bfa33244970ec127abceb Mon Sep 17 00:00:00 2001
From: datomo <dave.lengw@gmail.com>
Date: Sun, 7 Apr 2024 16:53:48 +0200
Subject: [PATCH] fix for rollback with data sources and fix for data source
 column removal

---
 .../rules/AllocationToPhysicalScanRule.java   | 21 +++++++++++++++++++
 .../db/catalog/impl/PolyCatalog.java          |  5 ++++-
 .../polypheny/db/webui/crud/LanguageCrud.java |  4 ++++
 3 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/org/polypheny/db/algebra/rules/AllocationToPhysicalScanRule.java b/core/src/main/java/org/polypheny/db/algebra/rules/AllocationToPhysicalScanRule.java
index 1c379df8a2..468042c5e8 100644
--- a/core/src/main/java/org/polypheny/db/algebra/rules/AllocationToPhysicalScanRule.java
+++ b/core/src/main/java/org/polypheny/db/algebra/rules/AllocationToPhysicalScanRule.java
@@ -16,6 +16,8 @@
 
 package org.polypheny.db.algebra.rules;
 
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Optional;
 import org.polypheny.db.adapter.AdapterManager;
 import org.polypheny.db.algebra.AlgNode;
@@ -25,9 +27,11 @@
 import org.polypheny.db.algebra.logical.lpg.LogicalLpgScan;
 import org.polypheny.db.algebra.logical.relational.LogicalRelScan;
 import org.polypheny.db.algebra.type.AlgDataType;
+import org.polypheny.db.algebra.type.AlgDataTypeField;
 import org.polypheny.db.catalog.entity.allocation.AllocationEntity;
 import org.polypheny.db.plan.AlgOptRule;
 import org.polypheny.db.plan.AlgOptRuleCall;
+import org.polypheny.db.rex.RexNode;
 import org.polypheny.db.schema.trait.ModelTraitDef;
 import org.polypheny.db.tools.AlgBuilder;
 
@@ -89,6 +93,10 @@ private static AlgNode handleDocumentEntity( AlgOptRuleCall call, Scan<?> scan,
     private AlgNode handleRelationalEntity( AlgOptRuleCall call, Scan<?> scan, AllocationEntity alloc ) {
         AlgNode alg = AdapterManager.getInstance().getAdapter( alloc.adapterId ).orElseThrow().getRelScan( alloc.id, call.builder() );
         if ( scan.getModel() == scan.entity.dataModel ) {
+            if ( scan.getTupleType().getFieldCount() != alg.getTupleType().getFieldCount() ) {
+                alg = reduce( alg, scan, call.builder() );
+            }
+
             alg = attachReorder( alg, scan, call.builder() );
         }
 
@@ -100,6 +108,19 @@ private AlgNode handleRelationalEntity( AlgOptRuleCall call, Scan<?> scan, Alloc
     }
 
 
+    private AlgNode reduce( AlgNode current, Scan<?> scan, AlgBuilder builder ) {
+        builder.push( current );
+
+        List<RexNode> projects = new ArrayList<>();
+        for ( AlgDataTypeField field : scan.getTupleType().getFields() ) {
+            if ( current.getTupleType().getField( field.getName(), true, false ) != null ) {
+                projects.add( builder.field( field.getName() ) );
+            }
+        }
+        return builder.project( projects ).build();
+    }
+
+
     private AlgNode attachReorder( AlgNode newAlg, Scan<?> original, AlgBuilder builder ) {
         if ( newAlg.getTupleType().equals( original.getTupleType() ) ) {
             return newAlg;
diff --git a/core/src/main/java/org/polypheny/db/catalog/impl/PolyCatalog.java b/core/src/main/java/org/polypheny/db/catalog/impl/PolyCatalog.java
index b96d5dae61..4b36738aa3 100644
--- a/core/src/main/java/org/polypheny/db/catalog/impl/PolyCatalog.java
+++ b/core/src/main/java/org/polypheny/db/catalog/impl/PolyCatalog.java
@@ -228,11 +228,14 @@ public synchronized void commit() {
 
 
     public void rollback() {
+        long id = snapshot.id();
         restoreLastState();
 
         log.debug( "rollback" );
 
-        updateSnapshot();
+        if ( id != snapshot.id() ) {
+            updateSnapshot();
+        }
 
     }
 
diff --git a/webui/src/main/java/org/polypheny/db/webui/crud/LanguageCrud.java b/webui/src/main/java/org/polypheny/db/webui/crud/LanguageCrud.java
index ad13011970..027943f220 100644
--- a/webui/src/main/java/org/polypheny/db/webui/crud/LanguageCrud.java
+++ b/webui/src/main/java/org/polypheny/db/webui/crud/LanguageCrud.java
@@ -261,6 +261,10 @@ public static void attachAnalyzerIfSpecified( QueryContext context, InformationO
 
     @NotNull
     public static ResultBuilder<?, ?, ?, ?> getRelResult( ExecutedContext context, UIRequest request, Statement statement ) {
+        if ( context.getException().isPresent() ) {
+            return buildErrorResult( statement.getTransaction(), context, context.getException().get() );
+        }
+
         Catalog catalog = Catalog.getInstance();
         ResultIterator iterator = context.getIterator();
         List<List<PolyValue>> rows = new ArrayList<>();