[ 
https://issues.apache.org/jira/browse/BEAM-13618?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Beam JIRA Bot updated BEAM-13618:
---------------------------------
    Labels:   (was: stale-assigned)

> Java BigQuery IO: DirectRead does not work with Beam Schema support.
> --------------------------------------------------------------------
>
>                 Key: BEAM-13618
>                 URL: https://issues.apache.org/jira/browse/BEAM-13618
>             Project: Beam
>          Issue Type: Bug
>          Components: io-java-gcp
>    Affects Versions: 2.35.0
>            Reporter: Daniel Oliveira
>            Priority: P2
>
> Currently in BigQueryIO, Reads with Beam Schema support (for example using 
> [readTableRowsWithSchema|https://github.com/apache/beam/blob/v2.35.0/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigquery/BigQueryIO.java#L553])
>  don't actually have Schema support if using DirectRead as a read method. 
> This appears to be because the expansion logic for DirectReads takes [a 
> different 
> path|https://github.com/apache/beam/blob/v2.35.0/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigquery/BigQueryIO.java#L1060]
>  that doesn't include any considerations for beam schemas ([example of the 
> code handling Beam schemas in the default 
> path|https://github.com/apache/beam/blob/v2.35.0/sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/bigquery/BigQueryIO.java#L1204]).
> Part of the reason for this is likely that the current approach to Beam 
> Schema support is to get a description of the BQ table's schema and then 
> convert it to a Beam schema. However, with DirectRead specific columns can be 
> excluded while reading, meaning that the Beam schema needed doesn't actually 
> convert directly to the table's schema, it would need to be constructed based 
> on the specific fields selected for the read.
> (As a side note, this is currently not documented anywhere, leading me to 
> believe this is an oversight or potential bug. I will add some documentation 
> indicating that schema support currently does not work with DirectRead.)



--
This message was sent by Atlassian Jira
(v8.20.1#820001)

Reply via email to