Postgres dump of only parts of tables for a dev snapshot

Question

On production our database is a few hundred gigabytes in size. For development and testing, we need to create snapshots of this database that are functionally equivalent, bu

Answer 1

On your larger tables you can use the COPY command to pull out subsets...

COPY (SELECT * FROM mytable WHERE ...) TO '/tmp/myfile.tsv'

COPY mytable FROM 'myfile.tsv'

https://www.postgresql.org/docs/current/static/sql-copy.html

You should consider maintaining a set of development data rather than just pulling a subset of your production. In the case that you're writing unit tests, you could use the same data that is required for the tests, trying to hit all of the possible use cases.