Fix: New Datafusion-cli streaming printing way should handle corner case for only one small batch which lines are less than max_rows

[zhuqi-lucas]

Which issue does this PR close?

• closes New Datafusion-cli streaming printing way should handle corner case for only one small batch which lines are less than max_rows #14920

Rationale for this change

When we only have one batch and size < max_rows, also size < preview limit, we should collect it at the end.

What changes are included in this PR?

When we only have one batch and size < max_rows, also size < preview limit, we should collect it at the end.

Add the collect logic at the end.

Are these changes tested?

Yes

Testing result

> select * from a;
Error during planning: table 'datafusion.public.a' not found
> CREATE EXTERNAL TABLE IF NOT EXISTS lineitem (
        l_orderkey BIGINT,
        l_partkey BIGINT,
        l_suppkey BIGINT,
        l_linenumber INTEGER,
        l_quantity DECIMAL(15, 2),
        l_extendedprice DECIMAL(15, 2),
        l_discount DECIMAL(15, 2),
        l_tax DECIMAL(15, 2),
        l_returnflag VARCHAR,
        l_linestatus VARCHAR,
        l_shipdate DATE,
        l_commitdate DATE,
        l_receiptdate DATE,
        l_shipinstruct VARCHAR,
        l_shipmode VARCHAR,
        l_comment VARCHAR
) STORED AS parquet
LOCATION '/Users/zhuqi/arrow-datafusion/benchmarks/data/tpch_sf10/lineitem';
0 row(s) fetched.
Elapsed 0.007 seconds.

> select l_comment from lineitem limit 1;
+--------------------------+
| l_comment                |
+--------------------------+
| nic packages. regular re |
+--------------------------+
1 row(s) fetched.
Elapsed 0.087 seconds.

Are there any user-facing changes?

[zhuqi-lucas]

The bug which is found when i testing the following ticket:

#14909

cc @alamb @2010YOUY01 @xudong963

[alamb]

Thank you @zhuqi-lucas

I wonder if there is any way we can write a test for this logic so we don't accidentally break it again 🤔

[zhuqi-lucas]

Thank you @alamb for review, i also add the testing case now!

[zhuqi-lucas]

The testing include the following test, which was empty before this PR.

> SELECT * FROM generate_series(1, 5) t1(v1) ORDER BY v1 DESC;
+----+
| v1 |
+----+
| 5  |
| 4  |
| 3  |
| 2  |
| 1  |
+----+
5 row(s) fetched.
Elapsed 0.003 seconds.

[alamb]

Thank you @zhuqi-lucas and @2010YOUY01 ❤️