How can I get odd numbered characters in a string using SQL

Question

I am playing with some encrypted data and I need to get the odd numbered characters from a string and populate into a column:

abcedfgh

to

acdg

Is it really possible to do it in SQL? I tried googling on this but couldn't find any search results.

Answer 1

SELECT REGEXP_REPLACE(mycolumn, '(.).', '\1')
FROM   mytable