Postgres
Reusable skills for extending coding assistants
npx -y skills add dversoza/claude-skills --skill postgresAssembled from the repository path, not quoted from the project. Check it against their README if it does not work.
2 things to look at
- no licenseNo license file was found in the repository. Code published without one is not open source by default, so using it at work is a question for whoever answers licensing questions where you are.
- 2 stars2 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.
What its author says it does
Copied from the file, not written here
Read-only PostgreSQL database querying, schema introspection, and query planning. Use when the user asks to query a database, look up data, check a table, describe a schema, list tables, show indexes, explain a query plan, or any other read-only PostgreSQL interaction. Triggers on requests like "query the users table", "show me the schema", "what tables are in staging", "run this SQL", "describe the orders table", "check the database", "how many rows in X", "explain this query".
SKILL.md
3.5 KB, as published. Nobody here has run it
Postgres
Read-only access to PostgreSQL databases via psql. All connections enforce default_transaction_read_only=on at the server level -- writes and DDL are rejected by PostgreSQL itself.
Connection Setup
The script resolves database aliases from a ```pg-databases``` fenced code block in the project's CLAUDE.local.md. It searches from the current working directory upward. Credentials never appear on the command line -- only the alias is passed as an argument.
To discover available aliases:
python3 ~/.claude/skills/postgres/scripts/pg_query.py list
If no CLAUDE.local.md exists or it has no pg-databases block, ask the user for connection details and suggest they add a block like this to their project's CLAUDE.local.md:
```pg-databases
staging=postgres://user:pass@staging-host:5432/myapp
local=postgres://localhost:5432/myapp_dev
analytics=postgres://analyst:pass@analytics-host:5432/warehouse
```
Remind the user that CLAUDE.local.md should be in .gitignore to keep credentials out of version control.
Do NOT pass connection URIs on the command line. Always use the alias.
Subcommands
All subcommands take a database alias as the first argument.
Introspection
python3 ~/.claude/skills/postgres/scripts/pg_query.py schemas staging # list non-system schemas
python3 ~/.claude/skills/postgres/scripts/pg_query.py tables staging # list tables in public schema
python3 ~/.claude/skills/postgres/scripts/pg_query.py tables staging --schema analytics # list tables in a specific schema
python3 ~/.claude/skills/postgres/scripts/pg_query.py describe staging users # columns, types, nullability
python3 ~/.claude/skills/postgres/scripts/pg_query.py describe staging analytics.events # schema-qualified table
python3 ~/.claude/skills/postgres/scripts/pg_query.py indexes staging users # indexes on a table
Queries
python3 ~/.claude/skills/postgres/scripts/pg_query.py query staging "SELECT id, name FROM users LIMIT 10"
python3 ~/.claude/skills/postgres/scripts/pg_query.py explain staging "SELECT id, name FROM users WHERE active = true"
All subcommands return JSON to stdout. Errors go to stderr as JSON with an error field.
Query Guidelines
- Always add
LIMITto queries unless the user explicitly asks for all rows or the query already includes one. Default toLIMIT 100. - Prefer specific columns over
SELECT *when the table structure is known (usedescribefirst if needed). - For large result sets, suggest the user narrow the query rather than removing the limit.
- Writes are impossible: the connection is read-only at the PostgreSQL session level. If a write is attempted, psql returns
ERROR: cannot execute X in a read-only transaction. Report this to the user and explain the read-only constraint. - When exploring an unfamiliar database, start with
schemasthentablesthendescribebefore running queries.