NGA-TRAN opened a new issue, #18250:
URL: https://github.com/apache/datafusion/issues/18250
### Is your feature request related to a problem or challenge?
This task is part of feature #18249, aimed at illustrating what a query’s
join graph looks like. We use TPC-H Q5 as the example.
### Describe the solution you'd like
TPC-H Query 5 involves 6 tables and 6 joins, as our example.
```SQL
select
n_name,
sum(l_extendedprice * (1 - l_discount)) as revenue
from
customer,
orders,
lineitem,
supplier,
nation,
region
where
c_custkey = o_custkey
and l_orderkey = o_orderkey
and l_suppkey = s_suppkey
and c_nationkey = s_nationkey
and s_nationkey = n_nationkey
and n_regionkey = r_regionkey
and r_name = 'ASIA'
and o_orderdate >= date '1994-01-01'
and o_orderdate < date '1995-01-01'
group by
n_name
order by
revenue desc;
```
## Join Graph
Since our focus is join order enumeration, we’ll represent the query as a
join graph:
- Tables are shown as circles
- Joins appear as edges between circles:
- Directed edges indicate many-to-one joins
- Undirected edges indicate many-to-many joins
- Columns inside a circle denote selection predicates (filters) on that table
- Orders table is filtered on o_orderdate with ~15% selectivity.
- Region table is filtered o r_name and 20% selectivity
- Group-by column: n_name.
- Order-by field: the aggregation
- Color coding reflects table partitioning, sort order, and size category
These properties illustrate factors that influence join enumeration in the
next section. They’re optional and can be extended or omitted based on specific
needs
<img width="336" height="380" alt="Image"
src="https://github.com/user-attachments/assets/d4198939-9df4-483a-937a-4b25ca143d97";
/>
### Describe alternatives you've considered
-
### Additional context
_No response_
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