nautechsystems/nautilus_trader · error

Failed to load account events: {e}

Error message

Failed to load account events: {e}

What it means

Thrown by `load_account` when the SQL query that fetches the account's persisted event rows fails (the `Err(e)` arm of the query result). The underlying sqlx/database error is wrapped with context naming the operation; the account cannot be loaded from the cache database.

Source

Thrown at crates/infrastructure/src/sql/queries.rs:1201

    /// # Errors
    ///
    /// Returns an error if assembling events or SQL operations fail.
    pub async fn load_account(
        pool: &PgPool,
        account_id: &AccountId,
    ) -> anyhow::Result<Option<AccountAny>> {
        let account_events = Self::load_account_events(pool, account_id).await;
        match account_events {
            Ok(account_events) => {
                if account_events.is_empty() {
                    return Ok(None);
                }
                let account = AccountAny::from_events(&account_events).map_err(|e| {
                    anyhow::anyhow!("Failed to assemble account {account_id} from events: {e}")
                })?;
                Ok(Some(account))
            }
            Err(e) => anyhow::bail!("Failed to load account events: {e}"),
        }
    }

    /// Loads and assembles all `AccountAny` entries via the provided `pool`.
    ///
    /// # Errors
    ///
    /// Returns an error if loading events or SQL operations fail.
    pub async fn load_accounts(pool: &PgPool) -> anyhow::Result<Vec<AccountAny>> {
        let mut accounts: Vec<AccountAny> = Vec::new();
        let account_ids: Vec<AccountId> = sqlx::query(
            r#"
            SELECT DISTINCT account_id FROM "account_event"
        "#,
        )
        .fetch_all(pool)
        .await
        .map(|rows| {

View on GitHub (pinned to 18893faf8b)

Solutions

1. Read the wrapped `e` in the error message to identify the underlying sqlx/Postgres error and fix that cause first.
2. Verify the connection string, network reachability, and that Postgres is running.
3. Run the database migrations so the expected tables/schema exist.
4. Grant the DB user SELECT permission on the account events tables.

// before load: verify DB reachability and schema
sqlx::query("SELECT 1 FROM account_events LIMIT 1").execute(&pool).await?;

match AccountQueries::load_account(&pool, account_id).await {
    Ok(Some(account)) => account,
    Ok(None) => return /* not cached */,
    Err(e) => {
        log::error!("account load failed: {e:#}");
        /* reconnect pool / run migrations / retry with backoff */
    }
}

When it happens

Trigger: Calling `AccountQueries::load_account(pool, account_id)` when the SELECT of account events fails: connection failure, wrong table schema (migrations not applied), permission denied, or the pool being closed/unreachable.

Common situations: Postgres not running or wrong connection string; database schema out of date after upgrading nautilus (missing migrations); the DB user lacking SELECT privileges; network/firewall issues in containerized deployments.

Understand the failure class

Background: Database query failed: Internal Server Error 500s wrapping SQL, Prisma, and connection failures — what to check first — this error's family across 16 libraries.

Related errors

• Implement FromRow for FuturesSpread
• Implement FromRow for OptionSpread
• Failed to validate nonce recovery ownership: {e}
• Execution transaction {transaction_hash} was not found for s
• Failed to load from execution_transaction table: {e}

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/6c954bda4a4124fe. Report an issue: GitHub.