HHH-14876 Fix BatchLoadSizingStrategy#determineOptimalBatchLoadSize()

hibernate-core/src/main/java/org/hibernate/dialect/Dialect.java

@@ -3074,13 +3074,17 @@ public abstract class Dialect implements ConversionContext {
 			if ( numberOfKeyColumns > 1 ) {
 				return paddedSize;
 			}
-			if ( paddedSize < getInExpressionCountLimit() ) {
-				return paddedSize;
+			final int inExpressionCountLimit = getInExpressionCountLimit();
+			if ( inExpressionCountLimit > 0 ) {
+				if ( paddedSize < inExpressionCountLimit ) {
+					return paddedSize;
+				}
+				else if ( numberOfKeys < inExpressionCountLimit ) {
+					return numberOfKeys;
+				}
+				return getInExpressionCountLimit();
 			}
-			else if ( numberOfKeys < getInExpressionCountLimit() ) {
-				return numberOfKeys;
-			}
-			return getInExpressionCountLimit();
+			return paddedSize;
 		}
 	};
 

hibernate-core/src/test/java/org/hibernate/orm/test/loading/multiLoad/MultiLoadSubSelectCollectionTest.java

@@ -88,25 +88,11 @@ public class MultiLoadSubSelectCollectionTest {
 						assertFalse( Hibernate.isInitialized( p.children ) );
 					}
 
-					// When the first collection is loaded, the full batch of 50 collections
+					// When the first collection is loaded, the full collection
 					// should be loaded.
 					Hibernate.initialize( list.get( 0 ).children );
 
-					for ( int i = 0; i < 50; i++ ) {
-						assertTrue( Hibernate.isInitialized( list.get( i ).children ) );
-						assertEquals( i + 1, list.get( i ).children.size() );
-					}
-
-					// The collections for the 51st through 56th entities should still be uninitialized
-					for ( int i = 50; i < 56; i++ ) {
-						assertFalse( Hibernate.isInitialized( list.get( i ).children ) );
-					}
-
-					// When the 51st collection gets initialized, the remaining collections should
-					// also be initialized.
-					Hibernate.initialize( list.get( 50 ).children );
-
-					for ( int i = 50; i < 56; i++ ) {
+					for ( int i = 0; i < 56; i++ ) {
 						assertTrue( Hibernate.isInitialized( list.get( i ).children ) );
 						assertEquals( i + 1, list.get( i ).children.size() );
 					}