Fixed #1085

flyway-core/src/main/java/org/flywaydb/core/internal/dbsupport/derby/DerbySchema.java

@@ -63,6 +63,11 @@ protected void doDrop() throws SQLException {
 
     @Override
     protected void doClean() throws SQLException {
+        List<String> triggerNames = listObjectNames("TRIGGER", "");
+        for (String statement : generateDropStatements("TRIGGER", triggerNames, "")) {
+            jdbcTemplate.execute(statement);
+        }
+
         for (String statement : generateDropStatementsForConstraints()) {
             jdbcTemplate.execute(statement);
         }

flyway-core/src/test/java/org/flywaydb/core/internal/dbsupport/derby/DerbyMigrationMediumTest.java

@@ -64,4 +64,13 @@ public void bitdata() throws Exception {
 
         assertEquals("1", flyway.info().current().getVersion().toString());
     }
+
+    @Test
+    public void trigger() throws Exception {
+        flyway.setLocations("migration/dbsupport/derby/sql/trigger");
+        flyway.migrate();
+
+        // Fails if triggers aren't cleaned properly
+        flyway.clean();
+    }
 }

flyway-core/src/test/resources/migration/dbsupport/derby/sql/trigger/V1__Trigger.sql

@@ -0,0 +1,38 @@
+--
+-- Copyright 2010-2015 Axel Fontaine
+--
+-- Licensed under the Apache License, Version 2.0 (the "License");
+-- you may not use this file except in compliance with the License.
+-- You may obtain a copy of the License at
+--
+--         http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+--
+
+CREATE TABLE TEST (
+ID INTEGER NOT NULL,
+NAME VARCHAR(128) NOT NULL,
+PRIMARY KEY (ID)
+);
+
+CREATE TABLE TEST_REFERENCE (
+REF_ID INTEGER NOT NULL,
+TEST_ID INTEGER NOT NULL,
+PRIMARY KEY (REF_ID),
+CONSTRAINT FK_TEST_ID FOREIGN KEY (TEST_ID) REFERENCES TEST (ID)
+);
+
+CREATE TRIGGER TRG_Del_Test AFTER DELETE ON TEST_REFERENCE
+REFERENCING OLD AS EXISTING
+FOR EACH ROW MODE DB2SQL
+DELETE FROM TEST
+WHERE ID = EXISTING.TEST_ID
+;
+
+INSERT INTO TEST VALUES (1, 'Test trigger');
+INSERT INTO TEST_REFERENCE VALUES (1, 1);