@@ -18,7 +18,9 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
+import com.google.cloud.Timestamp;
 import com.google.cloud.spanner.BackupId;
+import com.google.cloud.spanner.Database;
 import com.google.cloud.spanner.DatabaseAdminClient;
 import com.google.cloud.spanner.DatabaseId;
 import com.google.cloud.spanner.ErrorCode;
@@ -44,10 +46,11 @@
 @RunWith(JUnit4.class)
 @SuppressWarnings("checkstyle:abbreviationaswordinname")
 public class SpannerSampleIT {
+private static final int DBID_LENGTH = 20;
 // The instance needs to exist for tests to pass.
 private static final String instanceId = System.getProperty("spanner.test.instance");
-private static final String databaseId =
-formatForTest(System.getProperty("spanner.sample.database"));
+private static final String baseDbId = System.getProperty("spanner.sample.database");
+private static final String databaseId = formatForTest(baseDbId);
 static Spanner spanner;
 static DatabaseId dbId;
 static DatabaseAdminClient dbClient;
@@ -69,9 +72,28 @@ public static void setUp() throws Exception {
 spanner = options.getService();
 dbClient = spanner.getDatabaseAdminClient();
 dbId = DatabaseId.of(options.getProjectId(), instanceId, databaseId);
-dbClient.dropDatabase(dbId.getInstanceId().getInstance(), dbId.getDatabase());
-dbClient.dropDatabase(
-dbId.getInstanceId().getInstance(), SpannerSample.createRestoredSampleDbId(dbId));
+// Delete stale test databases that have been created earlier by this test, but not deleted.
+deleteStaleTestDatabases(instanceId, baseDbId);
+}
+
+static void deleteStaleTestDatabases(String instanceId, String baseDbId) {
+Timestamp now = Timestamp.now();
+Pattern samplePattern = getTestDbIdPattern(baseDbId);
+Pattern restoredPattern = getTestDbIdPattern("restored");
+for (Database db : dbClient.listDatabases(instanceId).iterateAll()) {
+if (TimeUnit.HOURS.convert(now.getSeconds() - db.getCreateTime().getSeconds(),
+TimeUnit.SECONDS) > 24) {
+if (db.getId().getDatabase().length() >= DBID_LENGTH) {
+if (samplePattern.matcher(toComparableId(baseDbId, db.getId().getDatabase())).matches()) {
+db.drop();
+}
+if (restoredPattern.matcher(toComparableId("restored", db.getId().getDatabase()))
+.matches()) {
+db.drop();
+}
+}
+}
+}
 }
 
 @AfterClass
@@ -399,8 +421,21 @@ public void run() {
 private static int countOccurrences(String input, String search) {
 return input.split(search).length - 1;
 }
+
+private static String toComparableId(String baseId, String existingId) {
+String zeroUuid = "00000000-0000-0000-0000-0000-00000000";
+int shouldBeLength = (baseId + "-" + zeroUuid).length();
+int missingLength = shouldBeLength - existingId.length();
+return existingId + zeroUuid.substring(zeroUuid.length() - missingLength);
+}
 
-private static String formatForTest(String name) {
-return name + "-" + UUID.randomUUID().toString().substring(0, 20);
+private static Pattern getTestDbIdPattern(String baseDbId) {
+return Pattern.compile(
+baseDbId + "-[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{8}",
+Pattern.CASE_INSENSITIVE);
+}
+
+static String formatForTest(String name) {
+return name + "-" + UUID.randomUUID().toString().substring(0, DBID_LENGTH);
 }
-}
+}

@@ -34,7 +34,6 @@
 import java.math.BigDecimal;
 import java.util.Collections;
 import java.util.Iterator;
-import java.util.UUID;
 import java.util.concurrent.ExecutionException;
 import org.junit.AfterClass;
 import org.junit.Before;
@@ -49,8 +48,8 @@
 public class SpannerStandaloneExamplesIT {
 // The instance needs to exist for tests to pass.
 private static String instanceId = System.getProperty("spanner.test.instance");
-private static String databaseId =
-formatForTest(System.getProperty("spanner.sample.database", "mysample"));
+private static String baseDatabaseId = System.getProperty("spanner.sample.database", "mysample");
+private static String databaseId = SpannerSampleIT.formatForTest(baseDatabaseId);
 private static DatabaseId dbId;
 private static DatabaseAdminClient dbClient;
 private static Spanner spanner;
@@ -78,7 +77,6 @@ public static void createTestDatabase() throws Exception {
 }
 }
 dbId = DatabaseId.of(options.getProjectId(), instanceId, databaseId);
-dbClient.dropDatabase(dbId.getInstanceId().getInstance(), dbId.getDatabase());
 dbClient
 .createDatabase(
 instanceId,
@@ -190,8 +188,4 @@ public void queryWithNumericParameter_shouldReturnResults() {
 runExample(() -> QueryWithNumericParameterSample.queryWithNumericParameter(client));
 assertThat(out).contains("4 35000");
 }
-
-static String formatForTest(String name) {
-return name + "-" + UUID.randomUUID().toString().substring(0, 20);
-}
-}
+}