the connecting role cannot create the schema [SQL0064]

SQLStreams keeps its tables in a schema of their own, sqlstreams by default, so the shared control-plane tables and the ten tables every stream creates never land beside your own. Client.System().Register - or the first stream Register, which registers the system - creates that schema before it creates anything else, and Postgres refused: the role in the connection string has no CREATE privilege on the database.

Nothing was created. No schema, no tables, no system row.

Either grant the role the privilege:

GRANT CREATE ON DATABASE orders_db TO app_user;

Or create the schema yourself - useful when the application role is deliberately not allowed to create schemas - and let the role work inside it:

CREATE SCHEMA sqlstreams;
GRANT USAGE, CREATE ON SCHEMA sqlstreams TO app_user;

CREATE on the schema is still needed after the first path too: SQLStreams creates a table per stream, and per stream partition, for as long as the system runs.

Choosing a different schema

ClientConfig.Schema moves every table somewhere else. One schema holds exactly one SQLStreams installation, so two schemas in the same database are two independent systems that share nothing.

client, err := sqlstreams.NewClient(ctx, pool,
	&sqlstreams.ClientConfig{Schema: "sqlstreams_staging"})
if err != nil {
	return err
}

The name has to be a lowercase unquoted identifier - it reaches CREATE SCHEMA and every statement’s table qualifier as written, so anything else is rejected by Validate rather than quoted.