Function deleteColumn

apps/sim/lib/table/columns/service.ts:289–361

(
  data: DeleteColumnData,
  requestId: string
)

 * @throws Error if table not found, column not found, or it's the last column
 */
export async function deleteColumn(
  data: DeleteColumnData,
  requestId: string
): Promise<TableDefinition> {
  const { def, stripKey } = await withLockedTable(data.tableId, async (table, trx) => {
    const schema = table.schema
    const columnIndex = schema.columns.findIndex((c) => columnMatchesRef(c, data.columnName))
    if (columnIndex === -1) {
      throw new Error(`Column "${data.columnName}" not found`)
    }

    if (schema.columns.length <= 1) {
      throw new Error('Cannot delete the last column in a table')
    }

    const targetColumn = schema.columns[columnIndex]
    const actualName = targetColumn.name
    const columnId = getColumnId(targetColumn)
    const ownerGroupId = targetColumn.workflowGroupId

    // Drop this column's reference (by id) from every group's outputs and
    // `columns` dependency. If the column is the last output of its parent
    // group, the group itself is also removed (a group with zero outputs is
    // invalid).
    let groupRemovedId: string | null = null
    const updatedGroups = (schema.workflowGroups ?? [])
      .map((group) => {
        let next = group
        if (ownerGroupId && group.id === ownerGroupId) {
          const remaining = group.outputs.filter((o) => o.columnName !== columnId)
          if (remaining.length === 0) {
            groupRemovedId = group.id
          }
          next = { ...next, outputs: remaining }
        }
        return stripGroupDeps(next, new Set([columnId]))
      })
      .filter((g) => g.id !== groupRemovedId)

    const updatedSchema: TableSchema = {
      ...schema,
      columns: schema.columns.filter((_, i) => i !== columnIndex),
      ...(updatedGroups.length > 0 ? { workflowGroups: updatedGroups } : {}),
    }
    const updatedMetadata = stripColumnIdsFromMetadata(
      table.metadata as TableMetadata | null,
      new Set([columnId])
    )
    assertValidSchema(updatedSchema, updatedMetadata?.columnOrder)

    const now = new Date()

    // Schema/metadata update commits now; the column's row-data storage is
    // reclaimed in the background (fire-and-forget) — reads never surface the
    // orphaned id since the column is already gone from the schema.
    await trx
      .update(userTableDefinitions)
      .set({ schema: updatedSchema, metadata: updatedMetadata, updatedAt: now })