I am using Ruby to call postgresql through the shell via a command like:
%x[ psql -A -F "," -o feeds/tmp.csv -f lib/sql/query.sql -v id_list="#{id_list}" ]
query.sql looks like but can be changed:
Select *
From tbl_test
Where id in (:id_list)
The query should resolve to:
Select *
From tbl_test
Where id in ('a','b','c')
Thanks in advance.
# before
-v id_list="#{id_list}"
# after
# `join` will separate the values in an array with the string provided
# `map...` the block given to map will surround each item with single quotes
-v id_list="#{id_list.map { |i| "'#{i}'" }.join(', ') }"
# When `id` is an INTEGER you want the `IN` list specified without quotes
# SELECT * FROM tbl_test WHERE id IN (1, 2, 3);
-v id_list="#{id_list.map(&:to_i).join(', ') }"
