How to change decimal separator from comma to full

问题:

I'm working with raw data that has a comma as the decimal separator rather than fullstop (3,99 instead of 3.99). Is there a way to convert this directly in redshift copy command rather than having to upload then change afterwards?

回答1:

There are two issues to consider:

• Field delimiters
• Replacing Characters

The default delimiter in the Amazon Redshift COPY command is a pipe character ( | ), unless the CSV option is used, in which case the default delimiter is a comma ( , ).

Thus, if your file is delimited by a non-comma character (eg a pip "|" symbol), then the comma in a number will not split across fields.

As to converting the comma into a decimal, this is not possible. You will need to load the field as a string, and then run an UPDATE command to copy the string into a numeric field (with a bit of character replacement too).

Alternatively, try to pre-process the file before loading into Redshift (eg through sed), so it is clean before loading into Redshift.