risingwavelabs/risingwave · error · ErrorCode::BindErrorRoot

Failed to bind expression: {expr}: {error}

Error message

Failed to bind expression: {expr}: {error}

What it means

`ErrorCode::BindErrorRoot` is the structured bind error carrying both the failing expression text (`expr`) and the underlying cause as `BoxedError` (`error`, marked `#[source]`). It is the preferred variant (per the 'only keep this one' TODO) so callers see exactly which expression failed to bind and why.

Source

Thrown at src/frontend/src/error.rs:121

        #[backtrace]
        #[source]
        BoxedError,
    ),
    // TODO(error-handling): there's a limitation that `#[transparent]` can't be used with `#[backtrace]` if no `#[from]`
    // So we emulate a transparent error with "{0}" display here.
    #[error("{0}")]
    RpcError(
        #[source]
        #[backtrace]
        // `tonic::transport::Error`, `TonicStatusWrapper`, or `RpcError`
        BoxedError,
    ),
    // TODO: use a new type for bind error
    // TODO(error-handling): should prefer use error types than strings.
    #[error("Bind error: {0}")]
    BindError(#[message] String),
    // TODO: only keep this one
    #[error("Failed to bind expression: {expr}: {error}")]
    BindErrorRoot {
        expr: String,
        #[source]
        #[backtrace]
        error: BoxedError,
    },
    #[error(transparent)]
    CastError(
        #[from]
        #[backtrace]
        CastError,
    ),
    #[error("Catalog error: {0}")]
    CatalogError(
        #[source]
        #[backtrace]
        #[message]
        BoxedError,

View on GitHub (pinned to 6469eb736d)

Solutions

1. Read the `expr` field to pinpoint the failing sub-expression and the chained `error` for the reason
2. Fix the identifier typo or qualify the column/table name
3. Insert explicit casts to satisfy the operator's signature
4. Verify the function/operator exists in RisingWave (some Postgres functions are unimplemented)

Example fix

-- before
SELECT amount + created_at FROM orders; -- Failed to bind expression: amount + created_at: type mismatch
-- after
SELECT amount + extract(epoch from created_at) FROM orders;

-- pre-check the exact expression on sample data
SELECT amount + extract(epoch from created_at) FROM orders LIMIT 1;

fn is_bind_root(e: &RwError) -> bool { matches!(e.get_code(), ErrorCode::BindErrorRoot { .. }) }

if let ErrorCode::BindErrorRoot { expr, error } = err.get_code() { eprintln!("expr `{expr}` failed: {error}"); }

When it happens

Trigger: Any expression in a statement that the binder cannot resolve or type-check: unknown columns/functions/operators, wrong argument types, unsupported operators on the given operand types.

Common situations: Typos in column names, referencing a column not present in the FROM scope, implicit casts that don't exist, using batch-only functions in streaming contexts.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Type mismatched between then clause and case
• {} must contain 1 argument
• Expr error: {0}
• Bind error: {0}
• Invalid reference: {0}

AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/bc4bd3c07bf0de16. Report an issue: GitHub.