Alternate solution to save as JSON datatype in postgres spring-boot + eclipselink - json

Question

I am using eclipselink 2.6 with spring-boot JPA for persistance in postgres.
I am persisting a List of objects as a JSON column in database.Acording to this solution: eclipselink + #convert(json) + postgres + list property
I am able to save the data in postgres.
When the column is null, I get this exception:
Caused by: org.postgresql.util.PSQLException: ERROR: column "sample_column" is of type json but expression is of type character varying
Hint: You will need to rewrite or cast the expression.
I can solve this issue by this answer:
Writing to JSON column of Postgres database using Spring / JPA
Q1: Is there an alternate solution other than setting this property stringtype=unspecified int url spring.datasource.url=jdbc:postgresql://localhost:5432/dbnam‌​e?stringtype=unspeci‌​fied
Q2: If not, How can I set stringtype=unspecified in application.prooerties of spring-boot rather than embedding it in the spring.datasource.url

Answer 1

The answer is yes, but is implementation-specific.
For example, in Tomcat, this attribute is called connectionProperties, you would therefore write:
spring.datasource.tomcat.connection-properties: stringtype=unspecified
From the Spring-Boot documentation.
It is also possible to fine-tune implementation-specific settings using their respective prefix (spring.datasource.tomcat., spring.datasource.hikari., spring.datasource.dbcp.* and spring.datasource.dbcp2.*). Refer to the documentation of the connection pool implementation you are using for more details.

Answer 2

If you are using spring-boot 1.4.1 or above,
add a data.sql file in resources folder,
-- IN H2 database, create a column as 'OTHER' data type,
-- if H2 fails to create a column as 'JSON' data type.
CREATE DOMAIN IF NOT EXISTS JSON AS OTHER;
This .sql file will be executed during startup of your application and will create a column with data type others in table for the 'json' data type columns in H2 database.