gh-yzou commented on code in PR #496: URL: https://github.com/apache/parquet-format/pull/496#discussion_r2159816890
########## LogicalTypes.md: ########## @@ -539,6 +544,26 @@ The sort order used for `INTERVAL` is undefined. When writing data, no min/max statistics should be saved for this type and if such non-compliant statistics are found during reading, they must be ignored. +#### INTERVAL_YEAR_MONTH + +`INTERVAL_YEAR_MONTH` is used to represent a year-month time interval, such as +`4 years and 6 months`. It must annotate an `int32` that stores the total number +of months as a signed integer, which represents the interval and can be negative. +The time duration is independent of any timezone. + +#### INTERVAL_DAY_TIME + +`INTERVAL_DAY_TIME` is used to represent a day-time time interval, such as +`5 days, 10 hours and 30 minutes`. It must annotate a 16-byte `FIXED_LEN_BYTE_ARRAY` +that stores the total number of nanoseconds representing the interval. The value is +a signed integer and can be negative to indicate backward duration. +The time interval is independent of any timezone. + +Based on the [ANSI SQL standard](https://docs.oracle.com/en/database/oracle/oracle-database/19/sqlrf/Data-Types.html#GUID-7690645A-0EE3-46CA-90DE-C96DF5A01F8F) definition of the INTERVAL data type and fields values, +an interval of 1 day is equivalent to 24 hours, regardless of the specific number of Review Comment: i think the DayTimeInterval sometimes are referred as duration to be more clear on the unit used, and the pandas TimeDelta can be mapped to DayTimeInterval type, which is one of the biggest use case also. The YearMonth is clearly different as duration as @lidavidm pointed out. @lidavidm ``` this detail should also probably be in parquet.thrift (reference to SQL standard probably isn't strictly necessary there, just how 1 day is defined). ``` is your suggestion to remove the SQL reference here? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
