Re: Create filter Expression from string

2021-02-11 Thread Josh Mayer
Troy, thanks, it would be great to take a look at how you used Python's AST to do it. Send over a link when you get a chance. Josh On Mon, Feb 8, 2021 at 7:22 PM Troy Zimmerman wrote: > I have a library that uses Python’s AST module to parse Python expressions > and map them to Arrow Dataset ex

Re: Create filter Expression from string

2021-02-11 Thread Josh Mayer
Kirill, I was assuming gandiva was using the same expression code as the datasets. If that's not the case then that issue isn't relevant. I don't have strong views on how the parsing is done. Is there any interest in this being added to the C++ or Python dataset api? Is there any point in me submi

Re: Create filter Expression from string

2021-02-08 Thread Troy Zimmerman
I have a library that uses Python’s AST module to parse Python expressions and map them to Arrow Dataset expressions. I could extract the AST bits into a repo if you’re interested. It’s really simple but could serve as inspiration. It allows us to do things like: table = path.read_table(“valid_

Re: Create filter Expression from string

2021-02-08 Thread Kirill Lykov
The jira issue is about gandiva. Do you mean filtering in this module only? If yes, I did some experiments with tatsu and gandiva instead of antlr. And it was pretty nice and clean to develop PoC for sql-like language. In c++, antlr model is a bit old school. Also I prefer PEG grammar over lalr. Do