TO_CHAR function not available in H2 database

I am using H2 database for integration test. The code is quiet old and is using JDBC queries instead. While running tests i am getting the error below ``` org.h2.jdbc.JdbcSQLException: Function "TO_CHAR" not found; SQL statement: ``` I can see that H2 does not implecitely supports TO_CHAR function. Is there any way to add a custom methor or should i think about moving to HSQL DB or any other database for testing purpose.