I want to execute multiple SQL file using flyway with same version.
Solution 1
I try multiple SQL script bind into single SQL script and execute it. But now after some days new script will come and I merge into before create SQL file. That show error. My requirement is I only execute one single SQL file and my database is going to update.
Is there any way to do that?
Solution 2
I try version name with timestamp but that is not satisfied ou requirement. I want only one SQL file and when I migrate then it successfully migrate SQL file as well as when I again migrate new script then it successfully migrate it but all of this process do in single script.
Is there any way to do it?
I am using FlyWay Version 4.2.0.
Flyway uses a history table (flyway_schema_history) to track which migrations were already applied. More than that, this table has a checksum column which is done based on the content of the migration, which means if you change it, checksum will fail and your application start also.
Maybe giving the reasons behind your choice would help to give you some light on helping you.
How to check through spring-boot that if the database schema is already present do not run but run if no matching schema. Can I do the following through spring-boot flyway integration.
DEV - already has the database tables matching the sql scripts (e.g V1_Baseline.sql has both table creation and reference data) so should not run this but will need to create the internal SCHEMA_VERSION table and make this script as already run so that V2_....sql will run next)
TEST - has tables that should not be dropped but the scripts need to be run and internal SCHEMA_VERSION table created.
PROD - this is empty. So no issues should be there (same as test i guess).
From flyway site I saw this:
flyway clean (cannot run - nothing should be dropped)
flyway baseline (i think this is the one I need? check if current db is matching then just make current scripts as baseline and dont run if not run the scripts)
Nothing concrete here on here spring io too and on baeldung too.
I think answer is here with baseline and doing some checks but not sure what works.
Baseline is indeed what you need here as it serves this exact purpose.
In production, we use SQL scripts (Postgres) to generate / update the schema. In my unit tests, I use configProperties.put("hibernate.hbm2ddl.auto", "create-drop"); in order to create the schema for my H2 database.
In order to isolate the unit tests better, I want to drop and recreate the database in between tests. I can wipe the H2 database with entityManager.createNativeQuery("DROP ALL OBJECTS").executeUpdate();, but how do I then get hibernate to re-create the schema?
Or is there an easy way to simply shut down H2 and create a new instance? I can create multiple instances by using "jdbc:h2:mem:"+UUID.randomUUID()+";MODE=DB2;" as my connection string, but I'm not sure how to shut down / destroy / clean up previous instances.
I use JDBC and created h2 database called usaDB from sql script. Then I filled all tables with jdbc.
The problem is that after I connect to usaDB at localhost:8082 I cannot see on the left tree
my tables. There is only INFORMATION_SCHEMA database and rootUser which I specified creating usaDB.
How to view the content of tables in my h2 database?
I tried query SELECT * FROM INFORMATION_SCHEMA.TABLES.
But it returned many table names except those I created. My snapshot:
I had the same issue and the answer seems to be really stupid: when you type your database name you shouldn't add ".h2.db" suffix, for example, if you have db file "D:\somebase.h2.db" your connection string should be like "jdbc:h2:file:/D:/somebase". In other way jdbc creates new empty database file named "somebase.h2.db.h2.db" and you see what you see: only system tables.
You can use the SHOW command:
Using this command, you can lists the schemas, tables, or the columns of a table. e.g.:
SHOW TABLES
This problem drove me around the twist and besides this page I read many (many!) others until I solved it.
My Use Case was to see how a SpringBatch project created in STS using :: Spring Boot :: (v1.3.1.RELEASE) was going to behave with the H2 database; to do the latter, I needed to be able to get the H2 console running as well to query the DB results of the batch run.
This is what I did and found out:
Created an Web project in STS using Spring Boot:
Added the following to the pom.xml of the latter:
Added a Spring configuration file as follows to the project:
This solves the Web project deficiencies in STS. If you run the project now, you can access the H2 console as follows: http://localhost:8080/console
Now create a SpringBatch project in STS as follows (the alternative method creates a different template missing most of the classes for persisting data. This method creates 2 projects: one Complete, and the other an initial. Use the Complete in the following.):
The SpringBatch project created with STS uses an in memory H2 database that it CLOSES once the application run ends; once you run it, you can see this in the logging output.
So what we need is to create a new DataSource that overrides the default that ships with the project (if you are interested, just have a look at the log messages and you will see that it uses a default datasource...this is created from:
o.s.j.d.e.EmbeddedDatabaseFactory with the following parameters:
Starting embedded database: url='jdbc:hsqldb:mem:testdb', username='sa')
So, it starts an in memory, and then closes it. You have no chance of seeing the data with the H2 console; it has come and gone.
So, create a DataSource as follows:
You can of course use a properties file to map the parameters, and profiles for different DataSource instances...but I digress.
Now, make sure you set the bit that the red arrow in the picture is pointing to, to a location on your computer where a file can be persisted.
Running the SpringBatch (Complete project) you should now have a db file in that location after it runs (persisting Person data)
Run the Web project you configured previously in these steps, and you WILL :=) see your data, and all the Batch job and step run data (et voila!):
Painful but rewarding. Hope it helps you to really BOOTSTRAP :=)
I have met exactly this problem.
From what you describe, I suppose that you connect your jdbc with the "real" h2 server, but you are connecting on web application to database by the wrong mode (embedded-in-memory mode, aka h2mem). It means that h2 will create a new database in-memory, instead of using your true database stored elsewhere.
Please make sure that when you connect to this database, you use the mode Generic H2 (Server), NOTGeneric H2 (Embedded). You can refer to the picture below.
Version of jar file and installed h2 database should be same.
If in case you have created and populated H2 database table using maven dependency in spring boot, then please do change the JDBC URL as jdbc:h2:mem:testdb while connecting to H2 using web console.
It is an old question, but I came across the same problem. Eventually I found out that the default JDBC URL is pointing a test server rather than my application. After correcting it, I could access the right DB.
I tried with both Generic H2 (Embedded) and the Generic H2 (Server) options, both worked as long as the JDBC URL: is provided correctly.
In grails 4.0.1 the jdbc URL for development is jdbc:h2:mem:devDb. Check your application.yml file for the exact URL.
For the people who are using H2 in embedded(persistent mode) and want to "connect" to it from IntelliJ(other IDEs probably apply too).
Using for example jdbc url as follows: jdbc:h2:./database.h2
Note, that H2 does not allow implicit relative paths, and requires adding explicit ./
Relative paths are relative to current workdir
When you run your application, your workdir is most likely set to your project's root dir
On the other hand, IDE's workdir is most likely not your project's root
Hence, in IDE when "connecting" to your database you need to use absolute path like: jdbc:h2:/Users/me/projects/MyAwesomeProject/database.h2
For some reason IntelliJ by default also adds ;MV_STORE=false. It disables MVStore engine which in fact is currently used by default in H2.
So make sure that both your application and your IDE use the same store engine, as MVStore and PageStore have different file layouts.
Note that you cannot "connect" to your database if your application is using it because of locking. The other way around applies too.
In my case the issue was caused by the fact that I didn't set the h2 username, password in java. Unfortunatelly, Spring didn't display any errors to me, so it was not easy to figure out. Adding this lines to dataSource method helped me fix the issue:
dataSource.setUsername("sa");
dataSource.setPassword("");
Also, I should have specified the schema when creating tables in schema.sql
Selecting Generic H2 (Server) solved for me. We tempted to use default Generic H2 (Embedded) which is wrong.
I periodically receive data that I use to update my database with. The external structure differs from my internal structure so what I end up doing is running the import and then running alter table commands. I do this manually. After I format it to my liking, I export the data and then import it into my existing schema.
My questions are:
1. How can I isolate the external SQL so that it does not adversely affect my database? Ideally, I would like to run it as another user in another database / workspace. Should I create a database temporarily and then drop it once this operation is complete?
Should I connect directly using JDBC to run all these queries since there will be a large sum of data? I am using Hibernate along with C3P0 to manage the primary connection.
Lastly, is there an API to automate/simplify exporting to SQL? If I go the JDBC route, I can iterate through each row and create the insert statements from that.
Any ideas?
Thanks,
Walter
IMO, its better to do that outside of Hibernate, using simple JDBC. Just create a connection for this thing, and execute all SQL statements. In the end close the connection. This way its handy to make a connection to another temporary database, if you choose this route. You will not need to configure all that into your Hibernate configuration.
Other way is to go with Hibernate and let it create the schema for you using entity objects and their mappings. This way you don't need to manually come up with the database structure required, it will be automatically created by Hibernate.