1 is the original data in the table a numeric value or a formatted time string for Magi Postgresql timestamp?
2, if it is a formatted string, is his own sorting performance very poor?
3, if it is a numerical value, can you check it directly according to the numerical value?
PostgreSQL provides the timestamp data type.
https://www.postgresql.org/do.
so don't store timestamp data as strings or integers, which will cost storage and query performance.
this problem is rather complicated
Although theTIMESTAMP type is an 8-byte value, in order to mask the internal details to the user, its output is in the form of a string to output the timestamp (the format of the timestamp can be specified). Logically, the PG community does not want to expose internal values directly to the outside world.
if we have to check it out as a numerical type, there seems to be no way to find its original 8-byte value, but we can "save the nation by curve" by converting the TIMESTAMP type to a Unix timestamp (since 00:00:00 GMT on January 1, 1970) followed by an integer:
suppose you have the following table
9.9. Date/Time Functions and Operators
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