Support for common SQL data analysis tools

Ref #4729

Metabase

Result: “Suspended cursor is not supported” Error at: https://github.com/edgedb/edgedb/blob/60380fd7ae75b0230234315ad897405061ac08f3/edb/server/protocol/pg_ext.pyx#L626-L628

I had to add support for parsing SET statement and resolving it to an empty relation. They are using:

SET extra_float_digits TO 3

I think we are probably save for ignore this specific SET statement.

Reproduce with local instance of edgedb and:

$ docker run -d -p 3000:3000 --name metabase --net=host metabase/metabase

Cluvio

Error: ERROR: suspended cursor is not supported

To reproduce: I used their cloud to connect to my VPS with edgedb development env and a public IP.

Dbt-cloud

Result:

Runtime Error

  dbt was unable to connect to the specified database.

  The database returned the following error:

  

    >Database Error

    unsupported SQL construct: unknown enum: {'TransactionStmt': {'kind': 'TRANS_STMT_BEGIN'}}

  

  Check your database credentials and try again. For more information, visit:

  https://docs.getdbt.com/docs/configure-your-profile

To reproduce: I used their cloud to connect to my VPS with edgedb development env and a public IP.

This means that we need transactions.

Redash

I gave up trying to deploy an instance and connect to plain Postgres.

Tablau

Result:

Can’t connect to PostgreSQL
Detailed Error Message
An error occurred while communicating with PostgreSQL
ERROR: unsupported SQL construct: unknown enum: {'TransactionStmt': {'kind': 'TRANS_STMT_BEGIN'}}

To reproduce: I used their cloud to connect to my VPS with edgedb development env and a public IP.

---

TODO:

• process SET and TRANSACTION statements and save them to the context of the client connection
• Suspended cursor

@fantix I’ll prepare pg-parser for parsing all these statements but I won’t implement the resolver - they should be processed before that and not even hit resolver or be queried in postgres.

I’ll also prepare ResolverOptions which will contain search_path.

[elprans]

I had to add support for parsing SET statement

We need to add proper tracking of session configuration. Some config options alter the behavior significantly, most importantly the text I/O of data, and we must support that. To properly support this, we must track configuration values set in a session and prefix each query with a set_config(..., is_local := true)

[elprans]

Let’s ban set_config for now and see what breaks.