apache / apache/arrow-java

[JDBC] Exception handling for non-simple types swallows actual error during processing

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Description

### Describe the bug, including details regarding any error messages, version, and platform.

It appears as though apache/arrow#39356 added support for better error messages when an error is encountered during JDBC processing. However, some `MinorType` such as Decimal (and various others) do not have an associated ArrowType and throw an exception trying to get the additional information leading to the original error being suppressed.

Decimal MinorType:
https://github.com/apache/arrow/blob/main/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java#L583

Callsite for suppressing error:
https://github.com/apache/arrow/blob/main/java/vector/src/main/java/org/apache/arrow/vector/types/Types.java#L821

called from consumer (where minorType's arrow type is null)
https://github.com/apache/arrow/blob/main/java/adapter/jdbc/src/main/java/org/apache/arrow/adapter/jdbc/consumer/CompositeJdbcConsumer.java#L55

```
java.lang.RuntimeException: Error occurred while consuming data.
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.consumeData(ArrowVectorIterator.java:121)
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.load(ArrowVectorIterator.java:164)
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.next(ArrowVectorIterator.java:183)
...
Caused by: java.lang.UnsupportedOperationException: Cannot get simple type for type DECIMAL
at org.apache.arrow.vector.types.Types$MinorType.getType(Types.java:821)
at org.apache.arrow.adapter.jdbc.consumer.CompositeJdbcConsumer.consume(CompositeJdbcConsumer.java:55)
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.consumeData(ArrowVectorIterator.java:107)
... 95 more
```

suppressed error (via debugger):
```
java.lang.UnsupportedOperationException: BigDecimal precision cannot be greater than that in the Arrow vector: 39 > 38
at org.apache.arrow.vector.util.DecimalUtility.checkPrecisionAndScale(DecimalUtility.java:99)
at org.apache.arrow.vector.DecimalVector.set(DecimalVector.java:365)
at org.apache.arrow.adapter.jdbc.consumer.DecimalConsumer.set(DecimalConsumer.java:79)
at org.apache.arrow.adapter.jdbc.consumer.DecimalConsumer$NullableDecimalConsumer.consume(DecimalConsumer.java:101)
at org.apache.arrow.adapter.jdbc.consumer.CompositeJdbcConsumer.consume(CompositeJdbcConsumer.java:50)
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.consumeData(ArrowVectorIterator.java:107)
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.load(ArrowVectorIterator.java:164)
at org.apache.arrow.adapter.jdbc.ArrowVectorIterator.next(ArrowVectorIterator.java:183)
```

It is somewhat difficult to come up with a simple reproduction, but I getting this error by rounding decimals that should be too large to fit into a `decimal(38,10)` -- if a decimal exceeds this (such as the numeric value of `99999999999999999999999999999.9999999999` which requires 39 digits of precision) this error is thrown.

This is happening on version 15.0.0 and up. (was not occurring in 14.0.X and below).

### Component(s)

Java

Contributor guide

Open the contributing guide

Research direction

Start with CompositeJdbcConsumer.consume, then inspect Types.java, DecimalConsumer.java, and ArrowVectorIterator.consumeData to trace how the original Decimal precision error is replaced. Reproduce a JDBC value exceeding decimal(38,10) and verify that processing reports the underlying precision error instead of the UnsupportedOperationException from MinorType.getType().

Written by the indexing model from the issue text.

Assessment

Tech stack
java
Domain
databases
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
48/100

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