HHH-19749 set the correct default decimal precision for both Oracle and SQL Server

Author: robwgreenjr

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

@@ -507,6 +507,11 @@ public boolean supportsInsertReturningGeneratedKeys() {
 		return true;
 	}
 
+	@Override
+	public int getDoublePrecision() {
+		return 38;
+	}
+
 	/**
 	 * type or {@link Types#TIME} type, and its default behavior
 	 * for casting dates and timestamps to and from strings is just awful.

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

@@ -346,6 +346,11 @@ public int getMaxIdentifierLength() {
 		return 128;
 	}
 
+	@Override
+	public int getDoublePrecision() {
+		return 38;
+	}
+
 	@Override
 	public void contributeTypes(TypeContributions typeContributions, ServiceRegistry serviceRegistry) {
 		super.contributeTypes( typeContributions, serviceRegistry );

hibernate-core/src/test/java/org/hibernate/orm/test/secondarytable/MergeCastNumericTest.java

@@ -0,0 +1,66 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.orm.test.secondarytable;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.SecondaryTable;
+import jakarta.persistence.Table;
+import org.hibernate.annotations.JdbcType;
+import org.hibernate.dialect.OracleDialect;
+import org.hibernate.dialect.SQLServerDialect;
+import org.hibernate.testing.orm.junit.EntityManagerFactoryScope;
+import org.hibernate.testing.orm.junit.JiraKey;
+import org.hibernate.testing.orm.junit.Jpa;
+import org.hibernate.testing.orm.junit.RequiresDialect;
+import org.hibernate.testing.orm.junit.Setting;
+import org.hibernate.type.descriptor.jdbc.NumericJdbcType;
+import org.junit.jupiter.api.Test;
+
+@Jpa(
+		annotatedClasses = {MergeCastNumericTest.Actor.class},
+		integrationSettings = {
+				@Setting(name = org.hibernate.cfg.AvailableSettings.SHOW_SQL, value = "true"),
+		}
+)
+@JiraKey("HHH-19749")
+@RequiresDialect(OracleDialect.class)
+@RequiresDialect(SQLServerDialect.class)
+class MergeCastNumericTest {
+
+	@Test
+	void test(EntityManagerFactoryScope scope) {
+		scope.inTransaction(
+			entityManager -> {
+				Actor actor = new Actor();
+				actor.salary = 5000.77d;
+
+				entityManager.persist( actor );
+				entityManager.flush();
+				entityManager.clear();
+
+				actor = entityManager.find( Actor.class, actor.id );
+				actor.salary = 5000.88d;
+
+				entityManager.flush();
+				entityManager.clear();
+			}
+		);
+	}
+
+	@Entity(name = "actor")
+	@Table(name = "PRINCIPAL")
+	@SecondaryTable(name = "SECONDARY")
+	public static class Actor {
+		@Id
+		@GeneratedValue
+		private Long id;
+		@Column(table = "SECONDARY", precision = 6, scale = 2)
+		@JdbcType(NumericJdbcType.class)
+		private double salary;
+	}
+}