0

I am currently taking nightly exports of a Postgres 10.5 database, but taking schema only for 2 very large tables that I don't need the data for. I am compressing the export when done, and would really like to use pg_dump's internal compression system moving forward due to it being much faster in my testing.

Here is the workflow that I am currently using:

pg_dump -U postgres -h example.com -T very_large_tbl -T large_tbl db > /tmp/mydbdump

pg_dump -U postgres -h example.com -s -t very_large_tbl -t large_tbl db >> /tmp/mydbdump

bzip2 -zc < /tmp/mydbdump > /tmp/compressed_dbdump.dat.bz2

The workflow requires the following guidelines:

  1. Tables very_large_tbl and large_tbl need to export with no data (schema only).
  2. All other tables need schema + data exported.
  3. The end result must be compressed

My current workflow follows these guidelines without issue. However in testing on other databases using pg_dump -F c has MUCH faster overall process timings versus exporting and then compressing afterwards.

From what I can tell, you cannot use -s in pg_dump to "pick and choose" which tables get schema-only. It's all or nothing. Am I wrong here?

My question is this:

Is it possible to export "some" tables as schema only while using the -F c option of pg_dump? Or perhaps is it possible to append to an existing dump that was compressed with -F c?

Even if the process has to take place in 2 parts, that's fine and I'm open to "out of the box" workarounds. Just wondering if it's at all possible.

1

Well like always I just had to go back to the documentation and study it closely.

pg_dump has a --exclude-table-data option.

So to exclude data for a table named my_table it's as simple as --exclude-table-data=my_table

This will dump the create info for the table, but will exclude any data within it.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.