What causes "Failed to get unsigned small integer" in SeaQL/sea-orm?

Make the column non-nullable or use COALESCE in the query.

Failed to get unsigned small integer

Error message

Failed to get unsigned small integer

What it means

In `from_sqlx_mysql_row_to_proxy_row`, a column typed "SMALLINT UNSIGNED" is decoded with `row.try_get::<u16>` and `.expect("Failed to get unsigned small integer")`. The panic occurs when sqlx cannot decode the cell as u16 — usually because the value is NULL but a non-Option type was requested, or the reported column type does not match the actual decoded value.

Source

Thrown at sea-orm-sync/src/driver/sqlx_mysql.rs:397

    use sqlx::{Column, Row, TypeInfo};
    crate::ProxyRow {
        values: row
            .columns()
            .iter()
            .map(|c| {
                (
                    c.name().to_string(),
                    match c.type_info().name() {
                        "TINYINT(1)" | "BOOLEAN" => {
                            Value::Bool(row.try_get(c.ordinal()).expect("Failed to get boolean"))
                        }
                        "TINYINT UNSIGNED" => Value::TinyUnsigned(
                            row.try_get(c.ordinal())
                                .expect("Failed to get unsigned tiny integer"),
                        ),
                        "SMALLINT UNSIGNED" => Value::SmallUnsigned(
                            row.try_get(c.ordinal())
                                .expect("Failed to get unsigned small integer"),
                        ),
                        "INT UNSIGNED" => Value::Unsigned(
                            row.try_get(c.ordinal())
                                .expect("Failed to get unsigned integer"),
                        ),
                        "MEDIUMINT UNSIGNED" | "BIGINT UNSIGNED" => Value::BigUnsigned(
                            row.try_get(c.ordinal())
                                .expect("Failed to get unsigned big integer"),
                        ),
                        "TINYINT" => Value::TinyInt(
                            row.try_get(c.ordinal())
                                .expect("Failed to get tiny integer"),
                        ),
                        "SMALLINT" => Value::SmallInt(
                            row.try_get(c.ordinal())
                                .expect("Failed to get small integer"),
                        ),
                        "INT" => {

View on GitHub (pinned to e29bcd1b41)

Solutions

Make the column non-nullable or use COALESCE in the query.
Decode as `Option<u16>` and map NULL to Value::SmallUnsigned(None).
Propagate the try_get error instead of panicking to identify the offending column.
Pin/align the sqlx version with sea-orm's dependency.

Example fix

// before
"SMALLINT UNSIGNED" => Value::SmallUnsigned(
    row.try_get(c.ordinal()).expect("Failed to get unsigned small integer"),
)
// after: tolerate NULL
"SMALLINT UNSIGNED" => Value::SmallUnsigned(
    row.try_get::<Option<u16>, _>(c.ordinal())
        .expect("Failed to get unsigned small integer"),
)

Defensive patterns

Strategy: validation

Validate before calling

// check NULL before decoding SMALLINT UNSIGNED as u16
if row.try_get_raw(c.ordinal())?.is_null() && c.type_info().name() == "SMALLINT UNSIGNED" {
    // handle NULL path
}

Try / catch

let v: Option<u16> = row.try_get(c.ordinal())?;

Prevention

Make SMALLINT UNSIGNED columns NOT NULL or coalesce defaults in SQL.
Include NULL rows in proxy integration tests.
Don't alias columns in ways that obscure the real type.
Verify sqlx type mappings after any dependency upgrade.

When it happens

Trigger: Proxy backend query against MySQL returning a SMALLINT UNSIGNED column that is NULL, or whose value fails u16 decoding (expression/CAST changing the effective type).

Common situations: Nullable SMALLINT UNSIGNED columns in proxy result rows; SELECT with computed columns whose type_info name matches but value decodes differently; sqlx version drift in MySQL type mappings.

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

AI-assisted analysis of SeaQL/sea-orm@e29bcd1b41 (2026-09-10). Data as JSON: /api/errors/687363ee9996d203. Report an issue: GitHub.