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Posted to issues@nifi.apache.org by bbende <gi...@git.apache.org> on 2017/09/19 14:16:50 UTC
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
GitHub user bbende opened a pull request:
https://github.com/apache/nifi-registry/pull/10
NIFIREG-18 Refactor MetadataProvider to use an embedded database
- Initial plumbing for H2 database
- Setup Flyway with initial migration to define tables
- Setup entity classes with repositories
- Setup unit testing for repositories
- Removed existing MetadataProvider concept
- Removed provider impl module and moved remaining pieces into framework
- Added MetadataService with DatabaseMetadataService implementation
- Refactored RegistryService to use MetadataService
- Introduced verbose flag on some end-points to control loading nested objects
- Added ability to pass down paging/sorting params
- Added endpoints for available fields
- Adding ItemResource and ability to retrieve all items, or items by bucket
- Changing from Set to List on retrieval methods
You can merge this pull request into a Git repository by running:
$ git pull https://github.com/bbende/nifi-registry NIFIREG-18
Alternatively you can review and apply these changes as the patch at:
https://github.com/apache/nifi-registry/pull/10.patch
To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:
This closes #10
----
commit 8f394aaaabd73bf9a077b5b41ce897015daadac7
Author: Bryan Bende <bb...@apache.org>
Date: 2017-09-19T14:01:24Z
NIFIREG-18 Initial plumbling for H2 database
- Setup Flyway with initial migration to define tables
- Setup entity classes with repositories
- Setup unit testing for repositories
- Removed existing MetadataProvider concept
- Removed provider impl module and moved remaining pieces into framework
- Added MetadataService with DatabaseMetadataService implementation
- Refactored RegistryService to use MetadataService
- Introduced verbose flag on some end-points to control loading nested objects
- Added ability to pass down paging/sorting params
- Added endpoints for available fields
- Adding ItemResource and ability to retrieve all items, or items by bucket
- Changing from Set to List on retrieval methods
----
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by asfgit <gi...@git.apache.org>.
Github user asfgit closed the pull request at:
https://github.com/apache/nifi-registry/pull/10
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140035681
--- Diff: nifi-registry-web-api/src/main/java/org/apache/nifi/registry/NiFiRegistryApiApplication.java ---
@@ -14,27 +14,41 @@
* See the License for the specific language governing permissions and
* limitations under the License.
*/
-package org.apache.nifi.registry.web;
+package org.apache.nifi.registry;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.support.SpringBootServletInitializer;
-import org.springframework.context.annotation.ComponentScan;
+
+import java.util.Properties;
/**
* Main class for starting the NiFi Registry Web API as a Spring Boot application.
*
- * By default, Spring Boot will only scan in the package this class is located in, so we set
- * @ComponentScan to the common parent package to find beans in other packages.
+ * This class is purposely in the org.apache.nifi.registry package since that is the common base
+ * package across other modules. This is done because spring-boot will use the package of this
+ * class to automatically scan for beans/config/entities/etc. and would otherwise require
+ * configuring custom packages to scan in several different places.
*/
@SpringBootApplication
-@ComponentScan("org.apache.nifi.registry")
public class NiFiRegistryApiApplication extends SpringBootServletInitializer {
+ public static final String NIFI_REGISTRY_PROPERTIES_ATTRIBUTE = "nifi-registry.properties";
+
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
- return application.sources(NiFiRegistryApiApplication.class);
+ final Properties fixedProps = new Properties();
+ fixedProps.setProperty("spring.jpa.hibernate.ddl-auto", "none");
+ fixedProps.setProperty("spring.jpa.hibernate.naming.physical-strategy", "org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl");
+
+ // turn on to debug
+ fixedProps.setProperty("spring.jpa.show-sql", "true");
+ fixedProps.setProperty("spring.h2.console.enabled", "true");
--- End diff --
Did you intend to commit these debug props or was that included accidentally?
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140072829
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/repository/BucketRepository.java ---
@@ -14,38 +14,21 @@
* See the License for the specific language governing permissions and
* limitations under the License.
*/
-package org.apache.nifi.registry.metadata;
+package org.apache.nifi.registry.db.repository;
-import java.util.Set;
+import org.apache.nifi.registry.db.entity.BucketEntity;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.PagingAndSortingRepository;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
/**
- * The metadata for a bucket, along with the metadata about any objects stored in the bucket, such as flows.
+ * Spring Data Repository for BucketEntity.
*/
-public interface BucketMetadata {
-
- /**
- * @return the identifier of this bucket
- */
- String getIdentifier();
-
- /**
- * @return the name of this bucket
- */
- String getName();
-
- /**
- * @return the timestamp of when this bucket was created
- */
- long getCreatedTimestamp();
-
- /**
- * @return the description of this bucket
- */
- String getDescription();
+public interface BucketRepository extends PagingAndSortingRepository<BucketEntity,String> {
- /**
- * @return the metadata about the flows that are part of this bucket
- */
- Set<FlowMetadata> getFlowMetadata();
+ @Query("SELECT b FROM BucketEntity b WHERE LOWER(b.name) = LOWER(:name)")
+ List<BucketEntity> findByName(@Param("name") String name);
--- End diff --
Great idea, I'll update to use that approach
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140031965
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/DataSourceFactory.java ---
@@ -0,0 +1,85 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.nifi.registry.db;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.nifi.registry.properties.NiFiRegistryProperties;
+import org.h2.jdbcx.JdbcConnectionPool;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+
+import javax.sql.DataSource;
+import java.io.File;
+
+/**
+ * Overriding Spring Boot's normal automatic creation of a DataSource in order to use the properties
+ * from NiFiRegistryProperties rather than the standard application.properties/yaml.
+ */
+@Configuration
+public class DataSourceFactory {
+
+ private static final String DB_USERNAME_PASSWORD = "nifireg";
--- End diff --
Is there any downside to having the username and password hardcoded? I suppose if an admin needs to secure the DB file they can use the OS files system permissions to prevent file access. Is there any other use case that a configurable user/pass would facilitate?
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140073748
--- Diff: nifi-registry-resources/src/main/resources/conf/logback.xml ---
@@ -68,6 +68,11 @@
<logger name="org.apache.nifi.registry" level="INFO"/>
+ <!-- To see SQL statements set this to DEBUG -->
+ <logger name="org.hibernate.SQL" level="INFO" />
+ <!-- To see the values in SQL statements set this to TRACE -->
+ <logger name="org.hibernate.type" level="INFO" />
+
--- End diff --
Good find, will investigate
---
[GitHub] nifi-registry issue #10: NIFIREG-18 Refactor MetadataProvider to use an embe...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on the issue:
https://github.com/apache/nifi-registry/pull/10
Thanks, I'll resolve the white space issue and merge to master
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140072867
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/repository/FlowRepository.java ---
@@ -0,0 +1,34 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.nifi.registry.db.repository;
+
+import org.apache.nifi.registry.db.entity.FlowEntity;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.PagingAndSortingRepository;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
+
+/**
+ * Spring Data Repository for FlowEntity.
+ */
+public interface FlowRepository extends PagingAndSortingRepository<FlowEntity,String> {
+
+ @Query("SELECT f FROM FlowEntity f WHERE LOWER(f.name) = LOWER(:name)")
+ List<FlowEntity> findByName(@Param("name") String name);
--- End diff --
Will update as above
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140088139
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/DataSourceFactory.java ---
@@ -0,0 +1,85 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.nifi.registry.db;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.nifi.registry.properties.NiFiRegistryProperties;
+import org.h2.jdbcx.JdbcConnectionPool;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+
+import javax.sql.DataSource;
+import java.io.File;
+
+/**
+ * Overriding Spring Boot's normal automatic creation of a DataSource in order to use the properties
+ * from NiFiRegistryProperties rather than the standard application.properties/yaml.
+ */
+@Configuration
+public class DataSourceFactory {
+
+ private static final String DB_USERNAME_PASSWORD = "nifireg";
--- End diff --
Yep, that works for me. Just wanted to verify it.
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140038396
--- Diff: nifi-registry-resources/src/main/resources/conf/logback.xml ---
@@ -68,6 +68,11 @@
<logger name="org.apache.nifi.registry" level="INFO"/>
+ <!-- To see SQL statements set this to DEBUG -->
+ <logger name="org.hibernate.SQL" level="INFO" />
+ <!-- To see the values in SQL statements set this to TRACE -->
+ <logger name="org.hibernate.type" level="INFO" />
+
--- End diff --
When I ran the app. I noticed Hibernate log output going to bootstrap.log instead of app.log. Is that intended?
Example output in bootstrap.log:
```
2017-09-20 13:27:34,585 INFO [NiFi logging handler] org.apache.nifi.registry.StdOut Hibernate: select bucketenti0_.id as id1_0_0_, bucketenti0_.created as created2_0_0_, bucketenti0_.description as descript3_0_0_, bucketenti0_.name as name4_0_0_ from BUCKET bucketenti0_ where bucketenti0_.id=?
```
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140073712
--- Diff: nifi-registry-web-api/src/main/java/org/apache/nifi/registry/NiFiRegistryApiApplication.java ---
@@ -14,27 +14,41 @@
* See the License for the specific language governing permissions and
* limitations under the License.
*/
-package org.apache.nifi.registry.web;
+package org.apache.nifi.registry;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.support.SpringBootServletInitializer;
-import org.springframework.context.annotation.ComponentScan;
+
+import java.util.Properties;
/**
* Main class for starting the NiFi Registry Web API as a Spring Boot application.
*
- * By default, Spring Boot will only scan in the package this class is located in, so we set
- * @ComponentScan to the common parent package to find beans in other packages.
+ * This class is purposely in the org.apache.nifi.registry package since that is the common base
+ * package across other modules. This is done because spring-boot will use the package of this
+ * class to automatically scan for beans/config/entities/etc. and would otherwise require
+ * configuring custom packages to scan in several different places.
*/
@SpringBootApplication
-@ComponentScan("org.apache.nifi.registry")
public class NiFiRegistryApiApplication extends SpringBootServletInitializer {
+ public static final String NIFI_REGISTRY_PROPERTIES_ATTRIBUTE = "nifi-registry.properties";
+
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
- return application.sources(NiFiRegistryApiApplication.class);
+ final Properties fixedProps = new Properties();
+ fixedProps.setProperty("spring.jpa.hibernate.ddl-auto", "none");
+ fixedProps.setProperty("spring.jpa.hibernate.naming.physical-strategy", "org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl");
+
+ // turn on to debug
+ fixedProps.setProperty("spring.jpa.show-sql", "true");
+ fixedProps.setProperty("spring.h2.console.enabled", "true");
--- End diff --
The way I thought this was working was that even with those set to true, the logging didn't take place unless you also changed the levels in logback.xml as mentioned in your next comment, but apparently that is not true since you saw the output in bootstrap.log :)
---
[GitHub] nifi-registry issue #10: NIFIREG-18 Refactor MetadataProvider to use an embe...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on the issue:
https://github.com/apache/nifi-registry/pull/10
@kevdoran I pushed a new commit that changed the repository methods to the spring-data naming convention, and I removed those two properties that were being set in the application class which seemed to eliminate the bootstrap logging, you can still enable the hibernate logging in logback.xml but it will only go to app log.
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by bbende <gi...@git.apache.org>.
Github user bbende commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140073136
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/DataSourceFactory.java ---
@@ -0,0 +1,85 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.nifi.registry.db;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.nifi.registry.properties.NiFiRegistryProperties;
+import org.h2.jdbcx.JdbcConnectionPool;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+
+import javax.sql.DataSource;
+import java.io.File;
+
+/**
+ * Overriding Spring Boot's normal automatic creation of a DataSource in order to use the properties
+ * from NiFiRegistryProperties rather than the standard application.properties/yaml.
+ */
+@Configuration
+public class DataSourceFactory {
+
+ private static final String DB_USERNAME_PASSWORD = "nifireg";
--- End diff --
This is the same approach taken in NiFi so I went with it, the thinking is that the database can never be run in server mode and exposed outside of the file on the server, so at that point you are down to file permissions.
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140031392
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/repository/FlowRepository.java ---
@@ -0,0 +1,34 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.
+ */
+package org.apache.nifi.registry.db.repository;
+
+import org.apache.nifi.registry.db.entity.FlowEntity;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.PagingAndSortingRepository;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
+
+/**
+ * Spring Data Repository for FlowEntity.
+ */
+public interface FlowRepository extends PagingAndSortingRepository<FlowEntity,String> {
+
+ @Query("SELECT f FROM FlowEntity f WHERE LOWER(f.name) = LOWER(:name)")
+ List<FlowEntity> findByName(@Param("name") String name);
--- End diff --
Same as above regarding `@Query` annotation -> `findByNameIgnoreCase`.
---
[GitHub] nifi-registry issue #10: NIFIREG-18 Refactor MetadataProvider to use an embe...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on the issue:
https://github.com/apache/nifi-registry/pull/10
@bbende I reviewed your two new commits. Both look good to me. Thanks for making those fixes.
-Pcontrib-check is complaining about some whitespace on an empty line:
```
[INFO] --- maven-checkstyle-plugin:2.15:check (check-style) @ nifi-registry-web-api ---
[WARNING] src/main/java/org/apache/nifi/registry/NiFiRegistryApiApplication.java[44] (regexp) RegexpSinglelineJava: Line has trailing whitespace.
```
Other than that, LGTM.
---
[GitHub] nifi-registry pull request #10: NIFIREG-18 Refactor MetadataProvider to use ...
Posted by kevdoran <gi...@git.apache.org>.
Github user kevdoran commented on a diff in the pull request:
https://github.com/apache/nifi-registry/pull/10#discussion_r140024359
--- Diff: nifi-registry-framework/src/main/java/org/apache/nifi/registry/db/repository/BucketRepository.java ---
@@ -14,38 +14,21 @@
* See the License for the specific language governing permissions and
* limitations under the License.
*/
-package org.apache.nifi.registry.metadata;
+package org.apache.nifi.registry.db.repository;
-import java.util.Set;
+import org.apache.nifi.registry.db.entity.BucketEntity;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.PagingAndSortingRepository;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
/**
- * The metadata for a bucket, along with the metadata about any objects stored in the bucket, such as flows.
+ * Spring Data Repository for BucketEntity.
*/
-public interface BucketMetadata {
-
- /**
- * @return the identifier of this bucket
- */
- String getIdentifier();
-
- /**
- * @return the name of this bucket
- */
- String getName();
-
- /**
- * @return the timestamp of when this bucket was created
- */
- long getCreatedTimestamp();
-
- /**
- * @return the description of this bucket
- */
- String getDescription();
+public interface BucketRepository extends PagingAndSortingRepository<BucketEntity,String> {
- /**
- * @return the metadata about the flows that are part of this bucket
- */
- Set<FlowMetadata> getFlowMetadata();
+ @Query("SELECT b FROM BucketEntity b WHERE LOWER(b.name) = LOWER(:name)")
+ List<BucketEntity> findByName(@Param("name") String name);
--- End diff --
This can be rewritten without the `@Query` annotation just by renaming the method to `findByNameIgnoreCase`, and then the generated spring-data-jpa code will produce the query you want.
The advantage is not having to write and maintain the SQL in the `@Query` annotation, which prevents vendor-specific SQL syntax from sneaking in over time. It might not be possible to avoid the `@Query` annotation for every repository method, for example if you need a specific query optimization that spring-data-jpa cannot generate. I still think limiting explicit SQL is good practice in order to keep open the possibility that someone might want to modify registry to use an alternative to H2.
---