wren-query

The user wants to run a Wren CLI command. $ARGUMENTS is the SQL query or instruction.

What to do

1. Check for ~/.wren/mdl.json and ~/.wren/connection_info.json using Read or Glob.

   • If either is missing, tell the user what's needed and show the format below.
   • If both exist, proceed directly.

2. Run the appropriate command based on what the user asked:

Intent	Command
Execute and return results	uv run wren --sql '...'
Translate to native SQL (no DB)	uv run wren dry-plan --sql '...'
Validate without fetching rows	uv run wren dry-run --sql '...'
Check SQL is valid	uv run wren validate --sql '...'

If wren is installed globally (not via uv), use wren directly instead of uv run wren.

1. Show the result and explain what happened.

---

Required files

Both files are auto-discovered from ~/.wren/.

mdl.json — semantic model

{
  "catalog": "wren",
  "schema": "public",
  "models": [
    {
      "name": "orders",
      "tableReference": { "schema": "mydb", "table": "orders" },
      "columns": [
        { "name": "order_id",  "type": "integer" },
        { "name": "total",     "type": "double" },
        { "name": "status",    "type": "varchar" }
      ],
      "primaryKey": "order_id"
    }
  ]
}

connection_info.json — connection info (include datasource field)

{
  "datasource": "mysql",
  "host": "localhost",
  "port": 3306,
  "database": "mydb",
  "user": "root",
  "password": "secret"
}

Supported datasource values: mysql, postgres, bigquery, snowflake, clickhouse, trino, mssql, databricks, redshift, oracle, duckdb.

---

Override flags

When needed, flags can override the defaults:

wren --sql '...' --mdl other-mdl.json --connection-file prod-connection_info.json
wren --sql '...' --output csv          # table (default) | csv | json
wren --sql '...' --limit 100

---

Common errors

Error	Fix
mdl.json not found	Create ~/.wren/mdl.json
connection_info.json not found	Create ~/.wren/connection_info.json with a datasource field
datasource key not found	Add "datasource": "mysql" to connection_info.json
unknown datasource 'X'	Check spelling; see supported values above
Connection refused	Confirm the DB is running and host/port are correct