t8y2/dbx · error

custom type %s.%s is an array companion type

Error message

custom type %s.%s is an array companion type

What it means

Returned by server.getTypeDetails in kingbase-go when the resolved type turns out to be the implicit _array companion (element type with typisdefined/array marker indicating the backing array type for another type). PostgreSQL-family catalogs expose array companion rows separately; the agent only reports the user-facing type, not its array shell.

Source

Thrown at agents/drivers/kingbase-go/kingbase_metadata.go:708

		return nil, fmt.Errorf("custom type %s.%s does not exist", schema, name)
	}
	var oid, typbasetype, typrelid, typelem, typcollation int64
	var typtype, typalign, typstorage string
	var typisdefined, typnotnull, typbyval bool
	var typdefaultbin, typdefault, inputFn, outputFn, receiveFn, sendFn, analyzeFn, comment, collname, relkind sql.NullString
	var typlen sql.NullInt64
	var typtypmod int64
	if err := rows.Scan(&oid, &typtype, &typisdefined, &typbasetype, &typnotnull, &typrelid, &typelem, &typcollation, &typdefaultbin, &typdefault, &typlen, &typbyval, &typalign, &typstorage, &typtypmod, &inputFn, &outputFn, &receiveFn, &sendFn, &analyzeFn, &comment, &relkind, &collname); err != nil {
		return nil, fmt.Errorf("failed to read type %s.%s: %w", schema, name, err)
	}
	if err := rows.Close(); err != nil {
		return nil, err
	}
	if !typisdefined {
		return nil, fmt.Errorf("custom type %s.%s is not fully defined", schema, name)
	}
	if typelem != 0 {
		return nil, fmt.Errorf("custom type %s.%s is an array companion type", schema, name)
	}
	kind, ok := customTypeKindFromCode(typtype)
	if !ok {
		return nil, fmt.Errorf("custom type %s.%s is a pseudo type (typtype=%s)", schema, name, typtype)
	}
	if relkind.Valid && relkind.String != "" && relkind.String != "c" {
		return nil, fmt.Errorf("%s.%s is the auto-generated row type of a relation, not an independent custom type", schema, name)
	}

	properties := customTypeCommonProperties(inputFn, outputFn, receiveFn, sendFn, analyzeFn, typlen, typbyval, typalign, typstorage)
	properties.DomainConstraints = []customTypeDomainConstraint{}
	details := &customTypeDetails{
		Name:       name,
		Schema:     schema,
		Kind:       kind,
		Comment:    nullStringPtr(comment),
		Members:    []customTypeMember{},
		Properties: properties,

View on GitHub (pinned to c0390bff16)

Solutions

1. Request the base user-defined type instead of its array companion
2. Query the element type via typelem linkage if the base name is unknown

When it happens

Trigger: Thrown at agents/drivers/kingbase-go/kingbase_metadata.go:708 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of t8y2/dbx@c0390bff16 (2026-09-05). Data as JSON: /api/errors/d6338aa2b08d5558. Report an issue: GitHub.