with_advisory_lock | Advisory locking for ActiveRecord | Database library

Your error message shows that the problem lies in the descriptive_statistics (third party) gem. I found this issue in the project's github page -- which appears to be exactly your problem.

It also appears the issue has got nothing to do with rails upgrading, but rather, upgrading ruby to 2.4+

As suggested on the github issue, you can resolve it by doing:

From Rails 5 - when we reference a model, index on the foreign_key is automatically created.

Just do it like below -

Are you turning off transactional tests for this test case? I'm working on something similar and that proved to be important to actually simulating the concurrency.

See uses_transaction https://api.rubyonrails.org/classes/ActiveRecord/TestFixtures/ClassMethods.html

If transactions are not turned off, Rails will wrap the entire test in a transaction and this will cause all the threads to share one DB connection. Furthermore, in Postgres a session-level advisory lock can always be re-acquired within the same session. From the docs:

If a session already holds a given advisory lock, additional requests by it will always succeed, even if other sessions are awaiting the lock; this statement is true regardless of whether the existing lock hold and new request are at session level or transaction level.

Based on that I'm suspecting that your lock is always able to be acquired and therefore the .first_or_create call is always executed which results in the intermittent RecordNotUnique exceptions.

The line

Did you check my_database.schema_migrations table? You may find that Rails has already marked this migration as executed.

See https://edgeguides.rubyonrails.org/active_record_migrations.html#old-migrations

The users table may not exist because it's possible it was deleted manually.

I have faced a similar issue and below error message is clearly explaining the issue.

[400] {"error":{"root_cause":[{"type":"illegal_argument_exception","reason":"The difference between max_gram and min_gram in NGram Tokenizer must be less than or equal to: 1 but was [49]. This limit can be set by changing the [index.max_ngram_diff] index level setting."}],"type":"illegal_argument_exception","reason":"The difference between max_gram and min_gram in NGram Tokenizer must be less than or equal to: 1 but was [49]. This limit can be set by changing the [index.max_ngram_diff] index level setting."},"status":400}

Basically, by Default, the difference between max_gram and min_gram in NGram Tokenizer can't be more than 1 and if you want you to change this, then in your index settings you need to change it by adding below setting.

t.timestamps doesn't accept timestamp name, just hash/keyword arguments:

timestamps(options = {})

Adds timestamps (created_at and updated_at) columns to the table.

t.timestamps(null: false) Docs

If you want to add expires_at, you need to add it using a correct date type (e.g. datetime:

It looks like you are trying to do this with a sqlite database in your local system, and sqlite does not have json support, try changing your database to either mysql, postgres or a database system that has json support.

Are you doing anything in an initializer that might affect the MoneyRails::Configuration#amount_column? Looks like the OptionsExtractor is missing a few things.