Budibase/budibase · error · HTTPError

Duplicate calculation on field "${schema.field}", calculatio

Error message

Duplicate calculation on field "${schema.field}", calculation type "${schema.calculationType}"

What it means

Validation guard for calculation views: each non-count-distinct combination of target field and calculation type may appear only once across the view's calculation fields. A duplicate (same field, same calculationType) is rejected with 400.

Source

Thrown at packages/server/src/sdk/workspace/views/index.ts:112

  const tableId = getTableIdFromViewId(viewId)
  return !isExternalTableID(tableId)
}

function guardDuplicateCalculationFields(view: Omit<ViewV2, "id" | "version">) {
  const seen: Record<string, Record<CalculationType, boolean>> = {}
  const calculationFields = helpers.views.calculationFields(view)
  for (const name of Object.keys(calculationFields)) {
    const schema = calculationFields[name]
    const isCount = schema.calculationType === CalculationType.COUNT
    const isDistinct = "distinct" in schema

    if (isCount && isDistinct) {
      // We do these separately.
      continue
    }

    if (seen[schema.field]?.[schema.calculationType]) {
      throw new HTTPError(
        `Duplicate calculation on field "${schema.field}", calculation type "${schema.calculationType}"`,
        400
      )
    }
    seen[schema.field] ??= {} as Record<CalculationType, boolean>
    seen[schema.field][schema.calculationType] = true
  }
}

function guardDuplicateCountDistinctFields(
  view: Omit<ViewV2, "id" | "version">
) {
  const seen: Record<string, Record<CalculationType, boolean>> = {}
  const calculationFields = helpers.views.calculationFields(view)
  for (const name of Object.keys(calculationFields)) {
    const schema = calculationFields[name]
    const isCount = schema.calculationType === CalculationType.COUNT
    if (!isCount) {

View on GitHub (pinned to a81a902e9a)

Solutions

Remove or rename the duplicate calculation entry so each field+calculationType pair is unique
Give one of the duplicates a different calculationType if both are needed
Distinct COUNT duplicates should use the distinct form, which is tracked separately

Example fix

// before
calculations: { rev1: { field: "revenue", calculationType: "sum" }, rev2: { field: "revenue", calculationType: "sum" } }
// after
calculations: { rev_sum: { field: "revenue", calculationType: "sum" }, rev_avg: { field: "revenue", calculationType: "avg" } }

Defensive patterns

Strategy: validation

Validate before calling

const seen = new Set()
for (const c of Object.values(view.calculations ?? {})) {
  if (c.calculationType === "count" && "distinct" in c) continue
  const key = `${c.field}:${c.calculationType}`
  if (seen.has(key)) throw new Error(`Duplicate calculation: ${key}`)
  seen.add(key)
}

Try / catch

try { await sdk.views.create(tableId, view) }
catch (e) {
  if (e instanceof HTTPError && e.status === 400 && /Duplicate calculation/.test(e.message)) {
    // dedupe view.calculations then retry
  } else throw e
}

Prevention

Enforce unique field+calculationType pairs when building the view UI
Deduplicate generated calculation schemas before submitting
Add client-side validation mirroring the server guard

When it happens

Trigger: Creating/updating a view whose calculation schema defines two named calculation fields pointing at the same schema.field with the same calculationType (excluding COUNT distinct, handled separately).

Common situations: Builder duplicating a calculation column without changing target field; scripted view generation producing repeated aggregates like sum(revenue) twice under different names.

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 Budibase/budibase@a81a902e9a (2026-08-29). Data as JSON: /api/errors/1811bfad12e36e35. Report an issue: GitHub.