diff --git a/psql/README.md b/psql/README.md index 08b594feb..b20200e42 100644 --- a/psql/README.md +++ b/psql/README.md @@ -50,6 +50,7 @@ psql "postgres://db-xxxx@pg-1.example.com:5432/db-xxxx?sslmode=require&sslnegoti - .pgpass - .psqlrc - How to Import / Export CSV +- How to Backup & Restore - Session Variables (& Encryption Keys) ### How to View Rows Vertically @@ -200,6 +201,61 @@ FROM "character_descriptions"; \copy "character_descriptions"("id", "character_name", "description") FROM './character_descriptions.csv' WITH (FORMAT csv, HEADER); ``` +### How to Backup & Restore + +To backup in a way that will be easy to restore: + +- save the schema separately from the data +- don't include database-specific roles or permissions +- store the password in `~/.pgpass` as described above + +Given these credentials: + +```sh +my_user="db_xxxx" +my_db="db_xxxx" +my_host="pg-1.example.com" +my_port="5432" +``` + +And these `pg_dump` commands: + +```sh +pg_dump --no-privileges --no-owner --schema-only --clean \ + --username "$my_user" --no-password --host "$my_host" --port "$my_port" \ + -f ./"$my_db".schema.drop.sql "$my_db" >&2 + +pg_dump --no-privileges --no-owner --schema-only \ + --username "$my_user" --no-password --host "$my_host" --port "$my_port" \ + -f ./"$my_db".schema.sql "$my_db" >&2 + +pg_dump --no-privileges --no-owner --data-only \ + --username "$my_user" --no-password --host "$my_host" --port "$my_port" \ + -f ./"$my_db".data.sql "$my_db" +``` + +You'll get your data is this format: + +```text +db_xxxx.schema.drop.sql # will replace (DELETE) all tables with empty tables +db_xxxx.schema.sql # will create new empty tables +db_xxxx.data.sql # will load data +``` + +To restore / copy to another database: + +```sh +new_user="db_yyyy" +new_db="db_yyyy" +psql "postgres://$new_user@$my_host:$my_port/$new_db" < ./db_xxxx.schema.sql +psql "postgres://$new_user@$my_host:$my_port/$new_db" < ./db_xxxx.data.sql +``` + +See the examples at: + +- https://github.com/bnnanet/pg-essentials?tab=readme-ov-file#psql-backup +- https://github.com/therootcompany/pg-xzbackup.sh + ### How to use Session Variables Given the example `psqlrc` above which creates per-db history and config files,