Spark: Spark SQL read from Snapshot ref

[hililiwei]

Reading data from a specified Ref in the following ways.

1. USE

USE { BRANCH \ TAG } refName

2. table path

SELECT*FROMtable.at_branch_{refName}
SELECT*FROMtable.at_branch_{refName}.at_timestamp__{timestamp}
SELECT*FROMtable.at_tag_{refName}

This is mainly in reference to our current implementation of time travel.

SELECT*FROMtable.at_timestamp__{timestamp}

It depends on #4428#5364

[dungdm93]

I prefer SELECT * FROM table@refName if it's possible

[hililiwei]

I prefer SELECT * FROM table@refName if it's possible

Unfortunately, Spark does not support this syntax.
I could try, but not optimistic.

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