[PARQUET-1095] [C++] Read and write Arrow decimal values

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: cpp-1.4.0
• Component/s: parquet-cpp
• Assignee: Phillip Cloud
• Reporter: Wes McKinney
• Created: 10/Sep/17 00:10
• Updated: 23/Jun/24 03:29
• Resolved: 20/Nov/17 04:19

Description

We now have 16-byte decimal values in Arrow which have been validated against the Java implementation. We need to be able to read and write these to Parquet format.

To make these values readable by Impala or some other Parquet readers may require some work. It expects the storage size to match the decimal precision exactly. So in parquet-cpp we will need to write the correct non-zero bytes into a FIXED_LEN_BYTE_ARRAY of the appropriate size.

We should validate this against Java Parquet implementations

Issue Links

• is depended upon by: ARROW-1398 [Python] No support reading columns of type decimal(19,4)
• links to: GitHub Pull Request #403