Inconsistent schema?

The following was created by casbin-dashboard in Postgres:
```
casbin=# select * from casbin_rule;
p_type | v0 | v1 | v2 | v3 | v4 | v5
--------+-------+-------+-------+----+----+----
p | alice | book1 | read | | |
p | bob | book2 | write | | |
g | alice | admin | | | |
(3 rows)
```
But when I go to pycasbin it seems to want an id column:
```
psycopg2.errors.UndefinedColumn: column casbin_rule.id does not exist
LINE 1: SELECT casbin_rule.id AS casbin_rule_id, casbin_rule.ptype A...
```
Are these projects compatible? Also hope to have casbin-server on the same database...

Start by comparing the casbin_rule schema shown from Postgres with the query generated by pycasbin, then check how casbin-dashboard defines or expects that table. Reproduce the missing-id error and determine whether casbin-server uses the same database schema. Done means establishing compatibility and documenting or fixing the schema mismatch.

Written by the indexing model from the issue text.