Modify Timestamps to Split Date and Time
When there is a field where the date and time are both needed, the values should be separated so that there is both a date field and a time field. Having date time in two fields assists in the dictionary encoding as the date and time fields can be separately sorted into columns where the values are the same, decreasing the number of dictionary entries. To further improve compression, only include the seconds if absolutely necessary, as add decreasing the cardinality will increase compression.
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