Extract Numeric Date Value from short Date Format in SQL

I am trying to convert short date format to numeric date format in SQL.

Here are the dates I am trying to convert: 16-Mar-20 18-Mar-20 12-Mar-20

I have seen many methods to re-format dates based on numeric numbers but I am working with a dataset which has varied date-types. To ensure smoothness, I wanted to know what’s the way to convert these numbers to numeric date. Note that even if I extract the day month and year individually I could multiply them with respective values to get the dates. Here’s what I have done: (Although I have tried multiple things but this is the one which has yielded me the closest result, Note that my end goal is to convert the date into numeric value)

FROM_UNIXTIME(`Start Date`, 'dd-MMM-yy') AS 'Date Numeric'

Here Start Date is formatted in the way I have mentioned above. (14-Mar-20).

Answer

UNIX_TIMESTAMP is what you need, but first you have do transform your data to a Date

UNIX_TIMESTAMP(STR_TO_DATE(`Start Date`, '%d-%b-%y'))

With

SELECT UNIX_TIMESTAMP(STR_TO_DATE( "14-Mar-20", "%d-%b-%y"))

You get

UNIX_TIMESTAMP(STR_TO_DATE( "14-Mar-20", "%d-%b-%y"))
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