[BUG] Default columns is also a reader feature, the PROTOCOL doc is wrong. #2790
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The docs here state that enabling Default Columns will prevent older versions without the Default Column feature from reading the table: https://docs.delta.io/3.1.0/delta-default-columns.html
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Previously the decision was to make it a write only feature. That changed? Or docs are incorrect? |
You're right, something with my testing was wrong. It does not block reader access for older delta versions, The documentation here incorrectly notes that "Enabling default column values for a table upgrades the Delta table version as a byproduct of enabling table features. This protocol upgrade is irreversible. Tables with default column values enabled can only be read in Delta Lake 3.1 and above." |
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I'll cancel this PR and open one up for the doc that should be fixed. thanks! |
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New PR opened here: #2794 |
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The docs here correctly state that enabling Default Columns will prevent older versions without the Default Column feature from reading the table: https://docs.delta.io/3.1.0/delta-default-columns.html
The PROTOCOL doc conflicts with the above. I tested and confirmed that Default Columns is a table feature that requires the reader to support.
Signed-off-by: Miles Cole m.w.c.360@gmail.com
Which Delta project/connector is this regarding?
Description
Documentation needs updating
How was this patch tested?
Just documentation
Does this PR introduce any user-facing changes?
No