Completely copying a postgres table with SQL

Question

DISCLAIMER: This question is similar to the stack overflow question here, but none of those answers work for my problem, as I will explain later.

I\'m t

Answer 1

WARNING:

All the answers which use pg_dump and any sort of regular expression to replace the name of the source table are really dangerous. What if your data contains the substring that you are trying to replace? You will end up changing your data!

I propose a two-pass solution:

1. eliminate data lines from the dump using some data-specific regexp
2. perform search-and-replace on the remaining lines

Here's an example written in Ruby:

ruby -pe 'gsub(/(members?)/, "\\1_copy_20130320") unless $_ =~ /^\d+\t.*(?:t|f)$/' < members-production-20130320.sql > copy_members_table-20130320.sql

In the above I am trying to copy "members" table into "members_copy_20130320". My data-specific regexp is /^\d+\t.*(?:t|f)$/

The above type of solution works for me. Caveat emptor...

edit:

OK, here's another way in pseudo-shell syntax for the regexp-averse people:

1. pg_dump -s -t mytable mydb > mytable_schema.sql
2. search-and-replace table name in mytable_schema.sql > mytable_copy_schema.sql

3. psql -f mytable_copy_schema.sql mydb

4. pg_dump -a -t mytable mydb > mytable_data.sql

5. replace "mytable" in the few SQL statement preceding the data section
6. psql -f mytable_data.sql mydb