I wonder if we can fit U256 into Decimal?

Decimal and BigDecimal are both mapped to the same type on PostgreSQL, I was wondering why the change in that too but if you look at the definition of Wei (which uses BigDecimal) that has not changed from the old version.

Another note on this, the BigDecimal -> Decimal was a change which was made by the entity generation of the updated sea-orm package, and has nothing do with any specific changes made to the schema.

I suppose that the definition of column type Wei did not change since it is specified in the native Postgres type: decimal, which is equivalent of numeric ("The types decimal and numeric are equivalent"). So, Wei defines the column type, not the type which is going to be used in Rust struct which is mapped to the record in the table.

I don't believe that Rust Decimal can contain all values possible in U256. Type Decimal supports only 96-bit integers. In contrast, BigDecimal internally contains a vector of digits (see BigUint type).

I wonder if it is possible to enable feature with-bigdecimal on Postgres driver?

Not from what I found though going through code and docs.

Their discord is pretty dead, but it's better than nothing so I've tried to ask there.

In general, I doubt you would be storing gas values that overflow the decimal type in rust, perhaps one thing we could do is swap it to bigint 🤔

I suppose we can commit prelude which was generated by generate_entities.

I am not sure what you mean by commit could you please specify?

If you run generate_entities, it will generate entities files. They will be the same as currently committed in this PR with the exception of prelude.rs file. I think that prelude.rs can be also added to this PR. Current one and the generate one are equivalent.

Ahhh, I get it now, the new prelude is added in this PR. It is just that the generated one has a line by line format, not a block format, I changed it back to the block format so we can use the allow_unused_imports on the whole block as before. You can see the update I did here ed6d556

But you are right, the generated one is the same as the old one so everything is fine in that regard. The edit is just so we avoid having the warnings from the generated prelude.rs

Hope that makes sense

I wonder if it produces the same database schema as before (i.e. old version vs new version)?

It appears so, I did the test which you mentioned in the issue of the description, which is to generate a schema on the old version, scrape a bit, then switch to the new version and continue scraping, everything worked fine

It is good that it works. It is not the test for this comment though (but a good test for that comment)

The test is mostly manual for this:

1. Start Postgres on one port.
2. Init schema there (init_db.rs) from main.
3. Start Postgres on a different port.
4. Init schema from this branch.
5. Compare the tables and field types.

Ah, okay, I have done that.

Old schema:

New schema:

And the BigDecimal -> Decimal change did not alter anything is the postges schema as we can see, the type is still numeric 78 which is the same as is set in the l20230309_types file