Details
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New Feature
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Status: Open
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Minor
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Resolution: Unresolved
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1.36.0
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None
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None
Description
Seems that this new kind of JOIN named AS OF is very useful for processing time-series data. Here is some example documentation from Snowflake: https://docs.snowflake.com/en/sql-reference/constructs/asof-join
The semantics is similar to a traditional join, but the result always contains at most one record from the left side, with the last​ matching record on the right side (where "time" is any value that can be compared for inequality). This can be expressed in SQL, but it looks very cumbersome, using a JOIN, a GROUP BY, and then an aggregation to keep the last value.