I want to create a SQL interface on top of a non-relational data store. Non-relational data store, but it makes sense to access the data in a relational manner.
I am looking into using ANTLR to produce an AST that represents the SQL as a relational algebra expression. Then return data by evaluating/walking the tree.
I have never implemented a parser before, and I would therefore like some advice on how to best implement a SQL parser and evaluator.
- Does the approach described above sound about right?
- Are there other tools/libraries I should look into? Like PLY or Pyparsing.
- Pointers to articles, books or source code that will help me is appreciated.
Update:
I implemented a simple SQL parser using pyparsing. Combined with Python code that implement the relational operations against my data store, this was fairly simple.
As I said in one of the comments, the point of the exercise was to make the data available to reporting engines. To do this, I probably will need to implement an ODBC driver. This is probably a lot of work.