windmill-labs/windmill · error

Unimplemented case

Error message

Unimplemented case

What it means

makeAlterTableQueries() walks the pending table-editor operations and switches on op.kind to render SQL. The default branch throws 'Unimplemented case' when an operation kind reaches the switch that no case handles — i.e. an operation type added to AlterTableOperation (or a corrupted/hand-built operation object) without a corresponding SQL renderer here.

Source

Thrown at frontend/src/lib/components/apps/components/display/dbtable/queries/alterTable.ts:150

					// Snowflake requires CONSTRAINT syntax with explicit name
					const constraintName = `${values.name}_pk`
					queries.push(
						`ALTER TABLE ${tableRef} ADD CONSTRAINT ${constraintName} PRIMARY KEY (${op.columns.join(', ')});`
					)
				} else {
					const notEnforced = dbType === 'bigquery' ? ' NOT ENFORCED' : ''
					queries.push(
						`ALTER TABLE ${tableRef} ADD PRIMARY KEY (${op.columns.join(', ')})${notEnforced};`
					)
				}
				break

			case 'dropPrimaryKey':
				queries.push(renderDropPrimaryKey(tableRef, dbType, op.pk_constraint_name))
				break

			default:
				throw new Error('Unimplemented case')
		}
	}

	return queries
}

function renderAlterColumn(tableRef: string, op: AlterColumnOperation, dbType: DbType): string[] {
	const queries: string[] = []
	const { changes, original } = op

	const baseDatatype = changes.datatype ?? original.datatype
	const datatypeLength = datatypeHasLength(baseDatatype)
		? (changes.datatype_length ?? original.datatype_length)
		: undefined
	const datatype = datatypeLength ? `${baseDatatype}(${datatypeLength})` : baseDatatype

	if (changes.datatype || changes.datatype_length) {
		queries.push(renderAlterDatatype(tableRef, original.name, datatype, dbType))

View on GitHub (pinned to e474e8803c)

Solutions

1. Inspect the offending operation in the thrown context (log values.operations) to see the unhandled kind.
2. Update Windmill frontend to matching versions on both sides if UI and query builder diverged.
3. If developing: add a case for the new op.kind in the switch (or remove the operation from the producer).
4. Validate op.kind against the union type before calling makeAlterTableQueries when building operations programmatically.

Example fix

// before
case 'dropPrimaryKey':
  queries.push(renderDropPrimaryKey(tableRef, dbType, op.pk_constraint_name))
  break
default:
  throw new Error('Unimplemented case')
// after
default:
  assertNever(op) // exhaustive check: surfaces the missing kind at compile time

const knownKinds = ['addColumn','dropColumn','alterColumn','addForeignKey','dropForeignKey','renameTable','addPrimaryKey','dropPrimaryKey']
const bad = values.operations.filter(op => !knownKinds.includes(op.kind))
if (bad.length) throw new Error('Unknown operation kinds: ' + bad.map(o => o.kind).join(','))

function isKnownOperation(op: { kind: string }): op is AlterTableOperation {
  return ['addColumn','dropColumn','alterColumn','addForeignKey','dropForeignKey','renameTable','addPrimaryKey','dropPrimaryKey'].includes(op.kind)
}

try {
  const queries = makeAlterTableQueries(values, dbType, schema)
} catch (e) {
  console.error('alter-table op dispatch failed', values.operations, e)
  throw e
}

When it happens

Trigger: Passing an AlterTableValues whose operations array contains an op.kind not among addColumn/dropColumn/alterColumn/addForeignKey/dropForeignKey/renameTable/addPrimaryKey/dropPrimaryKey — e.g. a new operation kind introduced upstream in the table editor but not handled in this switch, or an operation object with an undefined/typo'd kind.

Common situations: A version mismatch between the table-editor UI (emitting a new operation kind) and this query builder; plugin/scripted edits that push hand-crafted operations into the editor state; data corrupted in transit leaving kind undefined.

Related errors

• Unsupported database type: ${dbType}
• Original foreign key missing constraint name : ${JSON.string
• Unsupported database type
• Unsupported database type
• Unsupported database type: ${dbType}

AI-assisted analysis of windmill-labs/windmill@e474e8803c (2026-09-03). Data as JSON: /api/errors/aaa2335ebbc9a17e. Report an issue: GitHub.