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Krisztian Szucs updated ARROW-10168: ------------------------------------ Fix Version/s: (was: 2.0.0) 3.0.0 > [Rust] [Parquet] Extend arrow schema conversion to projected fields > ------------------------------------------------------------------- > > Key: ARROW-10168 > URL: https://issues.apache.org/jira/browse/ARROW-10168 > Project: Apache Arrow > Issue Type: Sub-task > Components: Rust > Affects Versions: 1.0.1 > Reporter: Neville Dipale > Assignee: Carol Nichols > Priority: Major > Labels: pull-request-available > Fix For: 3.0.0 > > Time Spent: 1h 20m > Remaining Estimate: 0h > > When writing Arrow data to Parquet, we serialise the schema's IPC > representation. This schema is then read back by the Parquet reader, and used > to preserve the array type information from the original Arrow data. > We however do not rely on the above mechanism when reading projected columns > from a Parquet file; i.e. if we have a file with 3 columns, but we only read > 2 columns, we do not yet rely on the serialised arrow schema; and can thus > lose type information. > This behaviour was deliberately left out, as the function > *parquet_to_arrow_schema_by_columns* does not check for the existence of > arrow schema in the metadata. -- This message was sent by Atlassian Jira (v8.3.4#803005)