wangyum edited a comment on pull request #32090:
URL: https://github.com/apache/spark/pull/32090#issuecomment-817106123
I think we should not support this case. It has potential data issues. For
example:
```scala
import org.apache.spark.sql.types.StructType
spark.sql("SELECT 999999999 AS
a").write.mode("overwrite").parquet("/tmp/SPARK-34212")
val df = spark.read.schema(StructType.fromDDL("a decimal(2,
0)")).parquet("/tmp/SPARK-34212")
df.write.saveAsTable("t1")
spark.sql("select a, a * a as a2, a * a * a as a3, a * a * a * a as a4
from t1").write.saveAsTable("t2")
spark.sql("select * from t2").show(false)
spark.sql("desc t2").show(false)
```
```
+---------+----+----+----+
|a |a2 |a3 |a4 |
+---------+----+----+----+
|999999999|null|null|null|
+---------+----+----+----+
+--------+-------------+-------+
|col_name|data_type |comment|
+--------+-------------+-------+
|a |decimal(2,0) |null |
|a2 |decimal(5,0) |null |
|a3 |decimal(8,0) |null |
|a4 |decimal(11,0)|null |
+--------+-------------+-------+
```
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
