Merge pull request #2504 from FOCONIS/sqlserver-delete-problem

Cannot delete bean with more than 2100 child beans on SqlServer

ebean-core/src/main/java/io/ebeaninternal/server/persist/DefaultPersister.java

@@ -1,6 +1,7 @@
 package io.ebeaninternal.server.persist;
 
 import io.ebean.*;
+import io.ebean.annotation.Platform;
 import io.ebean.bean.BeanCollection;
 import io.ebean.bean.BeanCollection.ModifyListenMode;
 import io.ebean.bean.EntityBean;
@@ -644,11 +645,25 @@ public final class DefaultPersister implements Persister {
     DeleteMode deleteMode = (permanent || !descriptor.isSoftDelete()) ? DeleteMode.HARD : DeleteMode.SOFT;
     return delete(descriptor, null, idList, transaction, deleteMode);
   }
-
+  
   /**
    * Delete by Id or a List of Id's.
    */
   private int delete(BeanDescriptor<?> descriptor, Object id, List<Object> idList, Transaction transaction, DeleteMode deleteMode) {
+    int rows = 0;
+    if (server.databasePlatform().isPlatform(Platform.SQLSERVER)) {
+      // SqlServer has a 2100 parameter limit, so delete max 2000 ids at once
+      // this gives space up to 100 more query parameters.
+      while (idList != null && idList.size() > 2000) {
+        rows += deleteBatch(descriptor, id, idList.subList(0, 2000), transaction, deleteMode);
+        idList = idList.subList(2000, idList.size());
+      }
+    }
+    rows += deleteBatch(descriptor, id, idList, transaction, deleteMode);
+    return rows;
+  }
+
+  private int deleteBatch(BeanDescriptor<?> descriptor, Object id, List<Object> idList, Transaction transaction, DeleteMode deleteMode) {
     SpiTransaction t = (SpiTransaction) transaction;
     if (t.isPersistCascade()) {
       BeanPropertyAssocOne<?>[] propImportDelete = descriptor.propertiesOneImportedDelete();

ebean-test/src/test/java/org/tests/delete/TestDeleteByQuery.java

@@ -7,6 +7,7 @@ import io.ebean.test.LoggedSql;
 import org.junit.jupiter.api.Test;
 import org.tests.model.basic.*;
 
+import java.util.ArrayList;
 import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -233,6 +234,17 @@ public class TestDeleteByQuery extends BaseTestCase {
 
     DB.save(contact);
 
+    // check if we can delete more than 2100 in a batch on SqlServer
+    List<Contact> moreContacts = new ArrayList<>();
+    for (int i = 0; i < 2200; i++) {
+      Contact c = new Contact();
+      c.setFirstName("DelByQueryFirstName");
+      c.setLastName("deleteMe");
+      c.setCustomer(all.get(0));
+      moreContacts.add(c);
+    }
+    DB.saveAll(moreContacts);
+
     DB.find(Contact.class).where().eq("firstName", "DelByQueryFirstName").delete();
 
     Contact contactFind = DB.find(Contact.class, contact.getId());