From a3207d65c16189871006a123ac87b619d47042e7 Mon Sep 17 00:00:00 2001
From: Mark Hale <mark.hale@physics.org>
Date: Fri, 27 Oct 2023 15:48:42 +0100
Subject: [PATCH] Add support for NAryUnion to evaluation statistics.

---
 .../optimizers/ExtendedEvaluationStatistics.java   | 14 ++++++++++++++
 .../gin/halyard/optimizers/NAryUnionOptimizer.java |  6 +++---
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/strategy/src/main/java/com/msd/gin/halyard/optimizers/ExtendedEvaluationStatistics.java b/strategy/src/main/java/com/msd/gin/halyard/optimizers/ExtendedEvaluationStatistics.java
index 8ab944cd7..788feb48f 100644
--- a/strategy/src/main/java/com/msd/gin/halyard/optimizers/ExtendedEvaluationStatistics.java
+++ b/strategy/src/main/java/com/msd/gin/halyard/optimizers/ExtendedEvaluationStatistics.java
@@ -1,6 +1,7 @@
 package com.msd.gin.halyard.optimizers;
 
 import com.google.common.collect.Iterables;
+import com.msd.gin.halyard.algebra.NAryUnion;
 import com.msd.gin.halyard.algebra.StarJoin;
 
 import java.io.IOException;
@@ -308,11 +309,24 @@ public void meetOther(QueryModelNode node) {
     			meet((TupleFunctionCall)node);
     		} else if (node instanceof StarJoin) {
     			meet((StarJoin)node);
+    		} else if (node instanceof NAryUnion) {
+    			meet((NAryUnion)node);
     		} else {
     			super.meetOther(node);
     		}
     	}
 
+        public void meet(NAryUnion node) {
+        	double card = 0.0;
+        	for (TupleExpr expr : node.getArgs()) {
+	            expr.visit(this);
+	            updateMap(expr);
+	            card += this.cardinality;
+        	}
+        	cardinality = card;
+            updateMap(node);
+        }
+
         public void meet(StarJoin node) {
         	TupleExpr sp = node.getArg(0);
         	sp.visit(this);
diff --git a/strategy/src/main/java/com/msd/gin/halyard/optimizers/NAryUnionOptimizer.java b/strategy/src/main/java/com/msd/gin/halyard/optimizers/NAryUnionOptimizer.java
index f936a0e31..7535c637a 100644
--- a/strategy/src/main/java/com/msd/gin/halyard/optimizers/NAryUnionOptimizer.java
+++ b/strategy/src/main/java/com/msd/gin/halyard/optimizers/NAryUnionOptimizer.java
@@ -20,11 +20,11 @@
 public class NAryUnionOptimizer implements QueryOptimizer {
 	private final int minUnions;
 
-	public NAryUnionOptimizer(int minJoins) {
-		if (minJoins < 1) {
+	public NAryUnionOptimizer(int minUnions) {
+		if (minUnions < 1) {
 			throw new IllegalArgumentException("Minimum unions must be greater than or equal to one");
 		}
-		this.minUnions = minJoins;
+		this.minUnions = minUnions;
 	}
 
 	@Override