---
title: Dates & Timezones
slug: redshift/dates-and-timezones
icon: {"lucideIcon":"CalendarClock"}
docTags: 
createdAt: 2026-10-01T12:31:17.937Z
---

### Timezones

Date/timestamp columns are not standardized across tables — some are UTC, some are Eastern European time (Digitail's primary operating timezone), some are already converted to the clinic's local timezone. Always check this table before filtering or grouping by date.

| Code  | Meaning                        |
| ----- | ------------------------------ |
| UTC   | Coordinated Universal Time     |
| EEDT  | Eastern European Daylight Time |
| LOCAL | Clinic local timezone          |

| Table.Column                                                | UTC | EEDT | LOCAL |
| ----------------------------------------------------------- | --- | ---- | ----- |
| `sale.created_at`                                           |     | ✓    |       |
| `sale.updated_at`                                           |     | ✓    |       |
| `sale.deleted_at`                                           |     | ✓    |       |
| `sale.taxable_at`                                           | ✓   |      |       |
| `sold_service_packages.created_at`                          |     | ✓    |       |
| `sold_service_packages.updated_at`                          |     | ✓    |       |
| `sold_service_packages.deleted_at`                          |     | ✓    |       |
| `treatments.created_at`                                     |     | ✓    |       |
| `treatments.updated_at`                                     |     | ✓    |       |
| `treatments.deleted_at`                                     |     | ✓    |       |
| `charges.date`                                              |     | ✓    | ✓     |
| `charges.made_at`                                           | ✓   |      |       |
| `charges.created_at`                                        |     | ✓    |       |
| `charges.updated_at`                                        |     | ✓    |       |
| `charges.deleted_at`                                        |     | ✓    |       |
| `payments.created_at`                                       |     | ✓    |       |
| `payments.updated_at`                                       |     | ✓    |       |
| `payments.deleted_at`                                       |     | ✓    |       |
| `appointment.datetime`                                      |     |      | ✓     |
| `new_file_cases.opened_at` / `.closed_at`                   |     | ✓    |       |
| `reception_notes.date` / `.due_date` / `.doc_date`          |     | ✓    |       |
| `custom_events.datetime_start` / `.datetime_end`            |     |      | ✓     |
| `custom_events.datetime_start_utc` / `.datetime_end_utc`    | ✓   |      |       |
| `reminder_protocol_usage.due_date` / `.administration_date` |     |      | ✓     |
| `reminder_protocol_usage.*_utc` variants                    | ✓   |      |       |

This table isn't exhaustive — if a column isn't listed and you're not sure, treat it as EEDT (the default for `created_at`/`updated_at`/`deleted_at` audit columns platform-wide) until confirmed otherwise, and flag it with us so we can add it here.

### Converting to clinic-local time

Where a column is UTC or EEDT and you need it in the clinic's actual local time, use `CONVERT_TIMEZONE`. For a clinic operating on Eastern Time (e.g. a Canadian clinic):

```sql
SELECT
    s.id,
    CONVERT_TIMEZONE('UTC', 'America/Toronto', s.taxable_at) AS taxable_at_local
FROM sale s;
```

If your table column is EEDT rather than UTC, convert from `'Europe/Bucharest'` as the source zone instead of `'UTC'`. Pick the IANA timezone name matching where your clinic actually operates — `clinics.timezone` on the [Operational](docId\:ihfOVSdsrTypRZRuq0DWW) page holds this per clinic if you're rolling up across locations.