alamb commented on issue #14974:
URL: https://github.com/apache/datafusion/issues/14974#issuecomment-2694390544
I agree in this case the limit is not necessary. I tried it in postgres to
double check
```sql
postgres=# create table foo(x int);
CREATE TABLE
postgres=# insert into foo values(1);
INSERT 0 1
postgres=# insert into foo values(2);
INSERT 0 1
postgres=# insert into foo values(3);
INSERT 0 1
postgres=# insert into foo values(4);
INSERT 0 1
postgres=# insert into foo values(5);
INSERT 0 1
postgres=# select count(*) from foo;
count
-------
5
(1 row)
postgres=# select count(*) from foo limit 2;
count
-------
5
(1 row)
```
However, in this case the limit node is likely not doing much work so
removing it may not save much time.
Note that postgres doesnt remove it either (the `Limit` is still there)
```sql
postgres=# explain select count(*) from foo limit 2;
QUERY PLAN
-------------------------------------------------------------------
Limit (cost=41.88..41.88 rows=1 width=8)
-> Aggregate (cost=41.88..41.88 rows=1 width=8)
-> Seq Scan on foo (cost=0.00..35.50 rows=2550 width=0)
(3 rows)
postgres=#
```
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