are there a function works as generate_series()of postgresql in datafusion?

[l1t1]

thanks

[jonahgao]

There is an array function with the same name, but it is not a table function like in PostgreSQL.

DataFusion CLI v36.0.0
❯ select generate_series(1,10);
+-----------------------------+
| range(Int64(1),Int64(10))   |
+-----------------------------+
| [1, 2, 3, 4, 5, 6, 7, 8, 9] |
+-----------------------------+
1 row in set. Query took 0.011 seconds.

❯ select * from generate_series(1,10);
Error during planning: table function 'generate_series' not found

You can implement it as a user-defined table function and register it in DataFusion. Here's an example.

[l1t1]

could modify the results of generate_series to including the upper bound parameter?
then the same results of postgresql and sqlites?

[l1t1]

range() excluding the upper bound
duckdb

D select generate_series(1,3);
┌───────────────────────┐
│ generate_series(1, 3) │
│        int64[]        │
├───────────────────────┤
│ [1, 2, 3]             │
└───────────────────────┘
D select range(1,3);
┌─────────────┐
│ range(1, 3) │
│   int64[]   │
├─────────────┤
│ [1, 2]      │
└─────────────┘

[l1t1]

please also add generate_series documents to https://arrow.apache.org/datafusion/user-guide/sql/scalar_functions.html

[SteveLauC]

In DataFusion, range and generate_series seem to be the same thing, and the function is called range, generate_series is just an alias.

[SteveLauC]

PR docs: document range() alias generate_series() filed.

[l1t1]

the unnest() function is also needed

D select unnest(range(1,3));
┌─────────────────────┐
│ unnest(range(1, 3)) │
│        int64        │
├─────────────────────┤
│                   1 │
│                   2 │
└─────────────────────┘

[jonahgao]

I created PR #9342 to address this issue.