HHH-19297 Register SingleStore json functions to community SingleStoreDialect

[oyeliseiev-ua]

HHH-19297
Small improvement for community SingleStoreDialect

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https://hibernate.atlassian.net/browse/HHH-19297

[beikov]

Instead of using ANY for JSON arguments, please use FunctionParameterType.IMPLICIT_JSON.

Also, instead of adding the dialect specific functions, it would probably be nicer if you could try to implement the "standardized" functions as described here for this dialect when possible/reasonable: https://docs.jboss.org/hibernate/orm/7.0/userguide/html_single/Hibernate_User_Guide.html#hql-functions-json

[beikov]

This is looking good already, but the current implementation doesn't seem to support all types of data in JSON yet. Also, checking just for instanceof UnparsedNumericLiteral<?> isn't really checking if an expression is a numeric. An expression obviously can also be arithmetic or come from a column etc.. I proposed a different solution to this typing issue.
I can also merge the PR as it is, though it's incomplete AFAICT. Let me know what you want.

[oyeliseiev-ua]

This is looking good already, but the current implementation doesn't seem to support all types of data in JSON yet. Also, checking just for instanceof UnparsedNumericLiteral<?> isn't really checking if an expression is a numeric. An expression obviously can also be arithmetic or come from a column etc.. I proposed a different solution to this typing issue. I can also merge the PR as it is, though it's incomplete AFAICT. Let me know what you want.

@beikov Thank you for your review. I'll try to make improvements based on your suggestions and will let you know.

[oyeliseiev-ua]

@beikov take a look please

[beikov]

This looks great! Thanks for putting in the effort to make this compatible with our standard functions :)

One last question. Do you run the hibernate-core testsuite against a SingleStore database? If you do, it might be nice to add an entry to docker_db.sh and local-build-plugins/src/main/groovy/local.databases.gradle to allow other users to also do that.

I have the feeling that if you try to e.g. set a JSON object as value on a JSON object, that the current logic might fail. Consider an HQL expression like json_set('{}', '$.a', json_array()).

AFAIU your code, it calls to_json() on the result of json_array(). I guess for the database, the result of json_array() is of type json, but in case it treats this as "string", the invocation might produce {"a":"[]"}, whereas it should produce {"a":[]}. This is something that could be caught by running the hibernate-core testsuite.

[oyeliseiev-ua]

This looks great! Thanks for putting in the effort to make this compatible with our standard functions :)

One last question. Do you run the hibernate-core testsuite against a SingleStore database? If you do, it might be nice to add an entry to docker_db.sh and local-build-plugins/src/main/groovy/local.databases.gradle to allow other users to also do that.

I have the feeling that if you try to e.g. set a JSON object as value on a JSON object, that the current logic might fail. Consider an HQL expression like json_set('{}', '$.a', json_array()).

AFAIU your code, it calls to_json() on the result of json_array(). I guess for the database, the result of json_array() is of type json, but in case it treats this as "string", the invocation might produce {"a":"[]"}, whereas it should produce {"a":[]}. This is something that could be caught by running the hibernate-core testsuite.

@beikov
I have the test suite configuration on a separate branch, intended for local execution only. I'm concerned about maintainability due to specific SingleStore limitations—many tests need to be marked as skipped or have their logic adjusted. If that's acceptable, I'd like to create a separate PR for this.

The latest commit was tested using:
org.hibernate.orm.test.function.json.* and
org.hibernate.orm.test.query.hql.JsonFunctionTests.java