Question

I have active_record setup to use a Postgresql database. One of the columns is a character varying[] (basically a varchar array).

Anyway, my import routine then reads a tab-delimited text file and inserts records. All is fine until I get to an array. The column that should be converted to an array is comma separated. But the line itself is tab separated.

A sample of the data I’m importing looks like (tab delimited):

Col1      Col2     Col3                  Col4
----------------------------------------------
Apple     Pear     Sweet,Round,Green     Fruit

Col3 is imported like (ruby): col3.split(/,/) which gives me an array in Ruby. But active_record bombs out with:

PG::Error: ERROR: array value must start with “{” or dimension information (ActiveRecord::StatementInvalid)

How can I insert that column correctly?
Also, sometimes, col3 will be NULL.

Answer 1

I was able to insert using the following Ruby code:

alternatenames = '{' + s[3].split(/,/).map {|n| '"' + n + '"'}.join(",") + '}'