In MYSQL, how to upload a csv file that contains a date in the format of '1/1/2020' properly into a DATE data type format (standard YYYY-MM-DD)

Question

I have a column of data, let's call it bank_date, that I receive from an external vendor as a csv file every day. As such the dates in that column show as '1/1/2020'.

I am trying to upload that raw csv file directly to SQL daily. We used to store the SQL bank_date format as text, but we have converted it to a Data data type, and now it keeps zero'ing out every time, with some sort of truncate / "datetime value incorrect" error.

I have now tested 17 different versions of utilizing STR_TO_date (mostly), CAST, and CONVERT, and feel like I'm close, but I'm not quite getting the syntax right.

Also for reference, I did find 2 other workarounds that are successful, but my boss specifically wants it uploaded and converted directly through the import process (not manipulating the raw csv data) for safety reasons. For reference:

• Workaround 1: Convert csv date column to the YYYY-MM-DD format and save file. The issue with this is that if you try to open that CSV file again, it auto-changes the date format back to the standard mm/dd/yyyy. If someone doesn't know to watch out for this and is re-opening the csv file to double check something, they're gonna find an error when they upload, and the problem is not easy to identify.
• Workaround 2:Create an extra dummy_date column in the table that is formatted as a text data type and upload as normal. Then copy and paste the data into the correct bank_date column using a str_to_date function as follows: UPDATE dummy_date SET bank_date = STR_TO_DATE(dummy_date, '%c/%e/%Y'); The issue with this is that it just creates extra unnecessary data that can be confused when other people may not know that 1 of the columns is not intended for querying.

Here is my current code:

USE database_name;

LOAD DATA LOCAL INFILE 'C:/Users/Shelly/Desktop/Date Import.csv'

INTO TABLE bank_table

FIELDS TERMINATED BY ',' ENCLOSED BY '"' LINES TERMINATED BY '\r\n' IGNORE 1 ROWS

(bank_date, bank_amount)

SET bank_date = str_to_date(bank_date,'%Y-%m-%d');

The "SET" line is what I cannot work out on syntax to convert a csv's 1/5/2020' to SQL's 2020-1-5 format. Every test I've made either produces 0000-00-00 or nulls the column cells. I'm thinking maybe I need to tell SQL how to understand the csv's format in order for it to know how to convert it. Newbie here and stuck.

Answer 1

You need to specify a format for a date that is in the file, not a "required" one:

SET bank_date = str_to_date(bank_date,'%c/%e/%Y');