goldmedal commented on PR #13028:
URL: https://github.com/apache/datafusion/pull/13028#issuecomment-2429558649

   > Disallow non-integer types in 
[e6d1297](https://github.com/apache/datafusion/commit/e6d1297cb9045f99cab21690335740853fd91507)
 . Fractional values are more complicated than I expected, let's handle them 
later. @2010YOUY01 @findepi
   
   I think the floating value is caused by the DataFusion casting behavior is 
different from others. I tried to cast a float to an integer.
   ### DataFusion
   ```
   DataFusion CLI v42.0.0
   > select 1.5::int;
   +--------------+
   | Float64(1.5) |
   +--------------+
   | 1            |
   +--------------+
   1 row(s) fetched. 
   Elapsed 0.055 seconds.
   
   > select 1.4::int;
   +--------------+
   | Float64(1.4) |
   +--------------+
   | 1            |
   +--------------+
   1 row(s) fetched. 
   Elapsed 0.001 seconds.
   ```
   ### Postgres
   ```
   test=# select 1.5::int;
    int4 
   ------
       2
   (1 row)
   
   test=# select 1.4::int;
    int4 
   ------
       1
   (1 row)
   ```
   ### DuckDB
   ```
   D select 1.5::int;
   ┌──────────────────────┐
   │ CAST(1.5 AS INTEGER) │
   │        int32         │
   ├──────────────────────┤
   │                    2 │
   └──────────────────────┘
   D select 1.4::int;
   ┌──────────────────────┐
   │ CAST(1.4 AS INTEGER) │
   │        int32         │
   ├──────────────────────┤
   │                    1 │
   └─────
   ```
   
   Postgres and DuckDB are rounding but DataFusion is round down.
   
   So, that's why `limit 1.5` only returns 1 row in DataFusion but returns 2 
rows in Postgres.
   


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