SeaQL/sea-orm · error

Failed to set value for {:?}: {e:?}

Error message

Failed to set value for {:?}: {e:?}

What it means

`ActiveModel::set` panics when the provided value cannot be converted into the column's expected type via `try_set`. The library deliberately panics (instead of returning a Result) because `set` is meant for trusted, compile-time-checked values; the message includes the column reference and the underlying conversion error.

Source

Thrown at sea-orm-sync/src/entity/active_model.rs:44

///   from `UPDATE`.
///
/// This makes ActiveModel ideal for partial updates: only the columns you
/// touch end up in the generated `UPDATE`.
pub trait ActiveModelTrait: Clone + Debug {
    /// The [`EntityTrait`] this ActiveModel belongs to.
    type Entity: EntityTrait;

    /// Take the [`ActiveValue`] of a column, leaving it as `NotSet`.
    fn take(&mut self, c: <Self::Entity as EntityTrait>::Column) -> ActiveValue<Value>;

    /// Read the [`ActiveValue`] of a column.
    fn get(&self, c: <Self::Entity as EntityTrait>::Column) -> ActiveValue<Value>;

    /// Set one column to `Set(v)`. Panics on type mismatch; prefer
    /// [`try_set`](Self::try_set) when the value comes from untrusted input.
    fn set(&mut self, c: <Self::Entity as EntityTrait>::Column, v: Value) {
        self.try_set(c, v)
            .unwrap_or_else(|e| panic!("Failed to set value for {:?}: {e:?}", c.as_column_ref()))
    }

    /// Set one column to `Set(v)` only if `v` differs from the current value,
    /// avoiding spurious `UPDATE` rewrites. Panics on type mismatch.
    fn set_if_not_equals(&mut self, c: <Self::Entity as EntityTrait>::Column, v: Value);

    /// Set one column to `Set(v)`, returning an error on type mismatch.
    fn try_set(&mut self, c: <Self::Entity as EntityTrait>::Column, v: Value) -> Result<(), DbErr>;

    /// Mark a column as `NotSet` so it is omitted from the next `INSERT` or
    /// `UPDATE`.
    fn not_set(&mut self, c: <Self::Entity as EntityTrait>::Column);

    /// `true` if the column is currently in the `NotSet` state.
    fn is_not_set(&self, c: <Self::Entity as EntityTrait>::Column) -> bool;

    /// A fresh ActiveModel with every column `NotSet`.
    fn default() -> Self;

View on GitHub (pinned to e29bcd1b41)

Solutions

1. Use `try_set` instead of `set` for untrusted values and handle the returned Result.
2. Fix the value type at the call site so it matches the entity column type declared in the Model.
3. For JSON input, validate/coerce fields with `set_from_json`'s fallible counterpart or validate the payload schema first.
4. If a column type changed, regenerate/review the entity definition and update all setters.

Example fix

// before
active.set(user::COLUMN.age, json_value.as_str().unwrap().to_string()); // wrong type
// after
active.try_set(user::COLUMN.age, json_value.as_i64().ok_or(...)? as i32)
    .expect("age must be i32");

// Validate/coerce untrusted values before set
fn coerce_age(v: &serde_json::Value) -> Option<i32> { v.as_i64().map(|n| n as i32) }
// or prefer the fallible API
active.try_set(user::COLUMN.age, value)?;

fn is_settable<T: IntoActiveValue<V>, V>(v: &T) -> bool { true } // rely on try_set's Result instead
fn try_set_guard<AM: ActiveModelTrait>(am: &mut AM, c: AM::Column, v: serde_json::Value) -> bool { am.try_set_from_json(c, v).is_ok() }

// set() panics; use try_set and handle the error
match active.try_set(user::COLUMN.email, value) {
    Ok(()) => {},
    Err(e) => eprintln!("invalid value for email: {e:?}"),
}

When it happens

Trigger: Calling `model.set(user::COLUMN.name, wrong_typed_value)` where `v`'s Rust type does not match the column type — e.g. passing an `i32` where the column is `String`, a `String` where a `DateTime`/decimal is expected, or `None` into a non-optional column. Also reached from `set_from_json` when a JSON field's value does not fit the column's type.

Common situations: Deserializing user-supplied JSON into an ActiveModel (`set_from_json`) with mismatched field types; refactoring a column type (int -> bigint, NaiveDateTime -> DateTime) without updating call sites; passing Option into a non-null column.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

• Failed to set value for {:?}: {e:?}
• Not mock connection
• Not proxy connection
• Cannot unwrap ActiveValue::NotSet
• Cannot borrow ActiveValue::NotSet

AI-assisted analysis of SeaQL/sea-orm@e29bcd1b41 (2026-09-10). Data as JSON: /api/errors/ef22616f1e5b5b6f. Report an issue: GitHub.