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Generating sample database data via Spring data.sql file

I would like to initialize my postgres database with data.sql file. I have created queries like:
insert into network_hashrate (
rep_date, hashrate
)
select
date_from - (s.a || ' hour')::interval,
s.a::double precision
from generate_series(0, 9999, 1) AS s(a);
Is it even possible to populate database using postgres functions in Spring? If not, what are my other options. I need like 10k sample records.

According to Spring Boot doc:
Spring Boot can automatically create the schema (DDL scripts) of your DataSource and initialize it (DML scripts). It loads SQL from the standard root classpath locations: schema.sql and data.sql, respectively.
So if you need to populate data only - just create data.sql file with your sql-scripts, place it to resources folder, then check spring.jpa.hibernate.ddl-auto in the application.properties to be set to none.
If you need more flexible solution, you can use Flyway. To use it - add its dependency to your project
<dependency>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-core</artifactId>
</dependency>
Turn the spring.jpa.hibernate.ddl-auto to validate.
Add spring.flyway.enabled=true to application.properties.
Place you 'migration' sql scripts to the 'default' location resources/db/migration folder. Call them like this, for example:
V1__schema_initialization.sql
V2__data_population.sql
When your spring boot app will be starting, Flyway check your database for missing schema and data then rolls these scripts sequentially.
More info about Flyway is here.

Seems you can run sql script after db scheme validate/created
Just name sql query file import.sql and spring should run it according this doc

You need something that will keep a track of what query ran and when ran. Also it should only run once not all the time when application startups.
liquibase is a option which can be used for that.
It will allow DDL as well as DML.
This link will give detail, How can you configure liquibase with spring
https://medium.com/#harittweets/evolving-your-database-using-spring-boot-and-liquibase-844fcd7931da

Spring Boot schema.sql - drop db schema on restart

Hi I'm using Spring Boot version 1.5.9.
When using Spring Boot to initialize schema.sql for mysql database, it works all fine and the database schema is getting created successfully. But on restart of the application this schema.sql script is executing again and the application fails to start because the tables already exist.
I tried spring.jpa.hibernate.ddl-auto=create-drop option in application.properties but it does not have any effect (probably because it only works for Hibernate entities which I'm not using)
Is there a way to have Spring Boot to re-create schema from schema.sql every time on restart if the database is not in-memory one?
GitHub:
https://github.com/itisha/spring-batch-demo/tree/database-input

According to the documentation you can simply ignore exceptions by setting spring.datasource.continue-on-error property to true
Spring Boot enables the fail-fast feature of the Spring JDBC
initializer by default, so if the scripts cause exceptions the
application will fail to start. You can tune that using
spring.datasource.continue-on-error.
or even turn it off with spring.datasource.initialize set to false
You can also disable initialization by setting spring.datasource.initialize to false.

A workaround could be, to change the create statements in your schema.sql
from
CREATE TABLE test .....
to
CREATE TABLE IF NOT EXISTS test ...
use the IF NOT EXISTS statements

turn off automatic schema creation to avoid conflicts: add this line in your application.properties
spring.jpa.hibernate.ddl-auto=none

Spring Auto configuration resulting in old MySQL dialect

I created a small POC app with spring boot, using hibernate (5.2.9) and maria db (10.1.19).
I had some sql dialect issues where my create/drop table SQL was using type=MyIasam but resolved that locally by setting the spring.jpa.properties.hibernate.dialect, however, when I deploy to the cloud (PCF) all of the cloud profile stuff kicks in, and I end up with hibernate deciding its dialect is going to be org.hibernate.dialect.MySQLDialect
this results in invalid SQL getting generated for creating new tables.
Note that I'm not really sure what else could be happening. This is a spring boot app (1.5.3) and the cloud profile is kicking in to do auto configuration. There's a bunch of properties injected. And I can't seem to get my dialect property to be respected.
This is a solid crushingly easy problem that is the escaping me.
Any ideas what I need to set, or provide as dependencies?
I tried removing all of the mysql dependencies, but then the connection string inject is jdbc:mysql... which i think may be part of the problem...

Play! JPA: Enforce not to create Entity on load

I am connecting to an external database (i.e. Oracle 10g) using my Play 1.2.4 application.
I have provided all the DB details in the application.conf file, then added the ojdbc.jar in the classpath and the connection seems to work fine. But the problem is everytime when the application access some data for the first time. it is trying to create the entity table (which is already present) and hence throws an exception.
I don't want to create any table since its already there with some data, hence how can I avoid this?
There might be some configuration to set in the application.conf for accessing the external database where the table is already available(I believe), kindly help me on this.
Below is the conf file:
application.mode=dev
%prod.application.mode=prod
db.url=jdbc:oracle:thin:#localhost:1521/orcl
db.driver=oracle.jdbc.OracleDriver
db.user=****
db.pass=****
#%test.module.cobertura=${play.path}/modules/cobertura
%test.application.mode=dev
%test.db.url=jdbc:h2:mem:play;MODE=MYSQL;LOCK_MODE=0
%test.jpa.ddl=create
%test.mail.smtp=mock
Note: Presently I am connecting to the external Oracle database and not with the embedded H2 database.

In your application.conf set the following property to none:
jpa.ddl=none

Hibernate database name change gives MySQLSyntaxErrorException: Table doesn't exist

I used to have a database called database and everything was working well using hibernate and its models.
I removed <property name="hibernate.hbm2ddl.auto"> to avoid update or create as it's a production server, we want to do it manually.
We recently switched to database2 and so we switched the hibernate configuration file and all the hibernate XML models.
`<class name="com.api.models.database.MmApplications" table="mm_applications" catalog="database2">`
but it keeps looking for database event if we migrated the database, the models and the connexion.
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'database.mm_applications' doesn't exist
Does someone can help me ?
UPDATE ----
Hibernate is connecting to the right database (database2), but there is a prefix as a prefix database. making the queries hitting the database instead of database2, and when I try to force the default_schema my queries become :
`... from database.database2.mm_applications ....`
Any idea?

My database is specified in the hibernate.connection.url property. Have you changed that also ? An example would be: jdbc:mysql://localhost/mydatabase
Also, instead of removing hibernate.hbm2ddl.auto then perhaps you should set its value to validate. That way hibernate will ensure that the datamodel matches the database schema.

I found the problem, It was an other application deployed on the same tomcat server using hibernate as well with another database (database) making a conflict with the new application ...
There is still something weird, by connecting to any database, hibernate will use the specified catalog in the hibernate models and so constructing the request using the catalog.table_name
Hope this help someone someday.