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Time Travel - Query an earlier version of the table

Time travel in Databricks

Delta Lake time travel allows you to query an older snapshot of a Delta Lake table.
For timestamp_string, only date or timestamp strings are accepted. For example, "2019-01-01" and "2019-01-01'T'00:00:00.000Z".
To query an older version of a table, specify a version or timestamp in a SELECT statement. For example, to query version 0 from the history above, use:
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SELECT * FROM events VERSION AS OF 0
or
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SELECT * FROM events TIMESTAMP AS OF '2019-01-29 00:37:58'
Note
Because version 1 is at timestamp '2019-01-29 00:38:10', to query version 0 you can use any timestamp in the range '2019-01-29 00:37:58' to '2019-01-29 00:38:09' inclusive.
DataFrameReader options allow you to create a DataFrame from a Delta Lake table that is fixed to a specific version of the table.
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df1 = spark.read.format("delta").option("timestampAsOf", timestamp_string).load("/delta/events")
df2 = spark.read.format("delta").option("versionAsOf", version).load("/delta/events")

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