Is the "$regex" search operator implemented ?

[DataHearth]

Hey !

I just started using PoloDB and it works like a charm ! Great software and it's very intuitive 😄 .

I have a quick question. The documentation specifies which search operator is implemented from the MongoDB engine (I guess it's the MongoDB engine). Does it includes the $regex operator ?

I want to search for a specific pattern inside the DB with a simple pattern like

{
"$regex": [{
  "name":  r".*name.*"g
}]

Thanks!

[vincentdchan]

Hi! This feature has not been implemented yet. However, if MongoDB implements it, I will add it to the roadmap. As I am currently working on implementing create_index, this will be considered a lower priority.

If you are interested, pull requests are also welcome.

[DataHearth]

@vincentdchan Hey! I started working on this feature on my free time ^^. But I'm quite lost with the codebase (firsttime with a big rust codebase ^^"). Do you know how I could debug the behavior of the evaluation on the $regex or any other query like evaluation ?

At first glance, it seems that the bson::bson::Regex is translated to plain text and not interpreted/evaluated for this case.

Thanks !

[vincentdchan]

Thanks for your interests! Implementing this is not a simple task, but I can provide you with some ideas.

1. Recognize $regex semantics in polodb_core/vm/subprogram.rs. You can try to understand the test print_complex_print.
2. Add an op to represents the regex tester in polodb_core/vm/op.rs
3. Modify subprogram to compile your regex tester op.
4. Implement the new OP in polodb_core/vm/vm.rs
5. Add unit tests

Don't know if it would be too difficult for you. You can give it a try~

[DataHearth]

Thanks the tips! I'll give it a try 😄.