clockworklabs/SpacetimeDB · error · syn::Error

scheduled tables must have a `#[primary_key] #[auto_inc] sch

Error message

scheduled tables must have a `#[primary_key] #[auto_inc] scheduled_id: u64` column

What it means

Scheduled-table validation found a `scheduled_at` time column but no `#[primary_key] #[auto_inc] scheduled_id: u64` column, which the scheduler requires as its handle. The error is emitted at the `scheduled` argument's span and names the exact required column, attributes, and type.

Source

Thrown at crates/bindings-macro/src/table.rs:1104

                return Err(syn::Error::new(
                    sched.span,
                    "scheduled table missing required columns; add these to your struct:\n\
                             #[primary_key]\n\
                             #[auto_inc]\n\
                             scheduled_id: u64,\n\
                             scheduled_at: spacetimedb::ScheduleAt,",
                ));
            }
            let scheduled_at_column = scheduled_at_column.ok_or_else(|| {
                syn::Error::new(
                    sched.span,
                    "scheduled tables must have a `scheduled_at: spacetimedb::ScheduleAt` column. \
                             if the column has a name besides `scheduled_at`, you can specify it with \
                             `scheduled(my_reducer, at = custom_scheduled_at)`",
                )
            })?;
            let primary_key_column = primary_key_column.ok_or_else(|| {
                syn::Error::new(
                    sched.span,
                    "scheduled tables must have a `#[primary_key] #[auto_inc] scheduled_id: u64` column",
                )
            })?;

            let reducer_or_procedure = &sched.reducer_or_procedure;
            let scheduled_at_id = scheduled_at_column.index;
            let desc = quote!(spacetimedb::table::ScheduleDesc {
                reducer_or_procedure_name: <#reducer_or_procedure as spacetimedb::rt::FnInfo>::NAME,
                scheduled_at_column: #scheduled_at_id,
            });

            let primary_key_ty = primary_key_column.ty;
            let scheduled_at_ty = scheduled_at_column.ty;
            let typecheck = quote! {
                spacetimedb::rt::scheduled_typecheck::<
                    #original_struct_ident,
                    <#reducer_or_procedure as spacetimedb::rt::FnInfo>::FnKind,

View on GitHub (pinned to 524b4487d9)

Solutions

1. Add `#[primary_key] #[auto_inc] scheduled_id: u64` to the struct
2. If the id column was renamed, restore the name `scheduled_id`
3. Ensure all three requirements are present: both attributes and the `u64` type

Example fix

// before
#[spacetimedb::table(accessor = reminders, scheduled(run_reminders))]
struct Reminders {
    scheduled_at: spacetimedb::ScheduleAt,
    note: String,
}

// after
#[spacetimedb::table(accessor = reminders, scheduled(run_reminders))]
struct Reminders {
    #[primary_key]
    #[auto_inc]
    scheduled_id: u64,
    scheduled_at: spacetimedb::ScheduleAt,
    note: String,
}

# scheduled tables missing the id column
grep -rl 'scheduled(' src/ | xargs -r grep -L 'scheduled_id' || echo OK

When it happens

Trigger: A scheduled table where `scheduled_at` (or an `at = ...` column) resolves but no primary-key column exists.

Common situations: Removing or renaming `scheduled_id`, or forgetting the `#[primary_key]`/`#[auto_inc]` attributes when hand-writing a scheduled table.

Related errors

• scheduled table missing required columns; add these to your
• scheduled tables must have a `scheduled_at: spacetimedb::Sch
• unions not supported
• must specify table accessor, e.g. `#[spacetimedb::table(acce
• a direct index must be paired with a `#[unique] constraint

AI-assisted analysis of clockworklabs/SpacetimeDB@524b4487d9 (2026-08-16). Data as JSON: /api/errors/e9a307664aef1bef. Report an issue: GitHub.