What causes "`{}` column not found in backfill table" in risingwavelabs/risingwave?

Ensure the target is the current internal backfill table with the row-count column (check its schema).

`{}` column not found in backfill table

Error message

`{}` column not found in backfill table

What it means

`BackfillInfo::new` locates the internal row-count column (`StreamTableScan::ROW_COUNT_COLUMN_NAME`) in the backfill table's schema. If the column is absent, it bails naming the missing column, since progress computation depends on it.

Source

Thrown at src/frontend/src/optimizer/rule/table_function_to_internal_backfill_progress.rs:193

struct BackfillInfo {
    job_id: JobId,
    fragment_id: FragmentId,
    table_id: TableId,
    row_count_column_index: usize,
    epoch_column_index: Option<usize>,
}

impl BackfillInfo {
    fn new(table: &TableCatalog) -> anyhow::Result<Self> {
        let Some(job_id) = table.job_id else {
            bail!("`job_id` column not found in backfill table");
        };
        let Some(row_count_column_index) = table
            .columns
            .iter()
            .position(|c| c.name() == StreamTableScan::ROW_COUNT_COLUMN_NAME)
        else {
            bail!(
                "`{}` column not found in backfill table",
                StreamTableScan::ROW_COUNT_COLUMN_NAME
            );
        };
        let epoch_column_index = table
            .columns
            .iter()
            .position(|c| c.name() == StreamTableScan::EPOCH_COLUMN_NAME);
        let fragment_id = table.fragment_id;
        let table_id = table.id;

        Ok(Self {
            job_id,
            fragment_id,
            table_id,
            row_count_column_index,
            epoch_column_index,
        })

View on GitHub (pinned to 6469eb736d)

Solutions

Ensure the target is the current internal backfill table with the row-count column (check its schema).
Upgrade to a version where the internal table schema matches what the rule expects.
Recreate the backfilling object to regenerate the internal table.
Use the documented progress-view API instead of the internal table function.

Defensive patterns

Strategy: try-catch

Validate before calling

// Check the internal table schema contains the row-count column before use
-- SELECT * FROM <internal_backfill_table> LIMIT 0; verify column present

Try / catch

match BackfillInfo::new(&table) {
    Ok(info) => /* proceed */,
    Err(e) => eprintln!("internal backfill schema mismatch: {e:#}"),
}

Prevention

Match RisingWave version between catalog snapshots and query engine
Inspect internal table columns before depending on them
Prefer documented progress views over internal tables

When it happens

Trigger: Same rule path as error 1443: the internal backfill TableCatalog's `columns` do not include the row-count column, so `position(...)` returns None.

Common situations: Internal table schema drift between versions, or querying a non-backfill internal table that lacks the synthetic row-count column.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/846e891a075d25c8. Report an issue: GitHub.