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Components of a date: such as the year or the month

Postgres
We can extract the year, the month, the day of the month and the day of the week. Times may be extracted in a similar way. The SQL Standard specifies the understandably unpopular EXTRACT function.	SELECT DATE_PART('YEAR',wk), DATE_PART('MONTH',wk), DATE_PART('DAY',wk), DATE_PART('DOW',wk) FROM totp WHERE song='Rio'
Specific to Postgres
In addition to the standard postgres supports the DATE_PART function.