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add dbt_valid_to_current #6308

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37 changes: 23 additions & 14 deletions website/docs/docs/build/snapshots.md
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Expand Up @@ -36,12 +36,6 @@ This order is now in the "shipped" state, but we've lost the information about w

## Configuring snapshots

:::info Previewing or compiling snapshots in IDE not supported

It is not possible to "preview data" or "compile sql" for snapshots in dbt Cloud. Instead, [run the `dbt snapshot` command](#how-snapshots-work) in the IDE.

:::

<VersionBlock lastVersion="1.8" >

- To configure snapshots in versions 1.8 and earlier, refer to [Configure snapshots in versions 1.8 and earlier](#configure-snapshots-in-versions-18-and-earlier). These versions use an older syntax where snapshots are defined within a snapshot block in a `.sql` file, typically located in your `snapshots` directory.
Expand Down Expand Up @@ -70,7 +64,7 @@ snapshots:
[updated_at](/reference/resource-configs/updated_at): column_name
[invalidate_hard_deletes](/reference/resource-configs/invalidate_hard_deletes): true | false
[snapshot_meta_column_names](/reference/resource-configs/snapshot_meta_column_names): dictionary

[dbt_valid_to_current](/reference/resource-configs/dbt_valid_to_current): string
```

</File>
Expand All @@ -87,13 +81,14 @@ The following table outlines the configurations available for snapshots:
| [check_cols](/reference/resource-configs/check_cols) | If using the `check` strategy, then the columns to check | Only if using the `check` strategy | ["status"] |
| [updated_at](/reference/resource-configs/updated_at) | If using the `timestamp` strategy, the timestamp column to compare | Only if using the `timestamp` strategy | updated_at |
| [invalidate_hard_deletes](/reference/resource-configs/invalidate_hard_deletes) | Find hard deleted records in source and set `dbt_valid_to` to current time if the record no longer exists | No | True |
| [dbt_valid_to_current](/reference/resource-configs/dbt_valid_to_current) | Set a custom future date for `dbt_valid_to` in new snapshot columns. When set, dbt will use this specified value instead of `NULL` for `dbt_valid_to` in the snapshot table. | No | string |
| [snapshot_meta_column_names](/reference/resource-configs/snapshot_meta_column_names) | Customize the names of the snapshot meta fields | No | dictionary |


- In versions prior to v1.9, the `target_schema` (required) and `target_database` (optional) configurations defined a single schema or database to build a snapshot across users and environment. This created problems when testing or developing a snapshot, as there was no clear separation between development and production environments. In v1.9, `target_schema` became optional, allowing snapshots to be environment-aware. By default, without `target_schema` or `target_database` defined, snapshots now use the `generate_schema_name` or `generate_database_name` macros to determine where to build. Developers can still set a custom location with [`schema`](/reference/resource-configs/schema) and [`database`](/reference/resource-configs/database) configs, consistent with other resource types.
- A number of other configurations are also supported (for example, `tags` and `post-hook`). For the complete list, refer to [Snapshot configurations](/reference/snapshot-configs).
- You can configure snapshots from both the `dbt_project.yml` file and a `config` block. For more information, refer to the [configuration docs](/reference/snapshot-configs).


### Add a snapshot to your project

To add a snapshot to your project follow these steps. For users on versions 1.8 and earlier, refer to [Configure snapshots in versions 1.8 and earlier](#configure-snapshots-in-versions-18-and-earlier).
Expand All @@ -112,6 +107,7 @@ To add a snapshot to your project follow these steps. For users on versions 1.8
unique_key: id
strategy: timestamp
updated_at: updated_at
dbt_valid_to_current: "to_date('9999-12-31')" # Specifies that current records should have `dbt_valid_to` set to `'9999-12-31'` instead of `NULL`.

```
</File>
Expand Down Expand Up @@ -172,6 +168,15 @@ This strategy handles column additions and deletions better than the `check` str

</Expandable>


<Expandable alt_header="Use dbt_valid_to_current for easier date range queries">

By default, `dbt_valid_to` is `NULL` for current records. However, if you set the [`dbt_valid_to_current` configuration](/reference/resource-configs/dbt_valid_to_current) (available in Versionless and 1.9 and higher), `dbt_valid_to` will be set to your specified value (such as `9999-12-31`) for current records.

This simplifies your SQL queries by avoiding `NULL` checks and allowing for straightforward date range filtering.

</Expandable>

<Expandable alt_header="Ensure your unique key is really unique">

The unique key is used by dbt to match rows up, so it's extremely important to make sure this key is actually unique! If you're snapshotting a source, I'd recommend adding a uniqueness test to your source ([example](https://github.com/dbt-labs/jaffle_shop/blob/8e7c853c858018180bef1756ec93e193d9958c5b/models/staging/schema.yml#L26)).
Expand Down Expand Up @@ -204,12 +209,14 @@ Snapshots can't be rebuilt. Because of this, it's a good idea to put snapshots i
### How snapshots work

When you run the [`dbt snapshot` command](/reference/commands/snapshot):
* **On the first run:** dbt will create the initial snapshot table — this will be the result set of your `select` statement, with additional columns including `dbt_valid_from` and `dbt_valid_to`. All records will have a `dbt_valid_to = null`.
* **On the first run:** dbt will create the initial snapshot table — this will be the result set of your `select` statement, with additional columns including `dbt_valid_from` and `dbt_valid_to`. All records will have a `dbt_valid_to = null` or the value specified in [`dbt_valid_to_current`](/reference/resource-configs/dbt_valid_to_current) if configured.
* **On subsequent runs:** dbt will check which records have changed or if any new records have been created:
- The `dbt_valid_to` column will be updated for any existing records that have changed
- The updated record and any new records will be inserted into the snapshot table. These records will now have `dbt_valid_to = null`
- The `dbt_valid_to` column will be updated for any existing records that have changed.
- The updated record and any new records will be inserted into the snapshot table. These records will now have `dbt_valid_to = null` or the value configured in `dbt_valid_to_current`.

Note, these column names can be customized to your team or organizational conventions using the [snapshot_meta_column_names](#snapshot-meta-fields) config.
#### Note
- These column names can be customized to your team or organizational conventions using the [snapshot_meta_column_names](#snapshot-meta-fields) config.
- If you have set the `dbt_valid_to_current` configuration option, then instead of `NULL`, the `dbt_valid_to` field in future records will be set to your specified value (such as `9999-12-31`).

Snapshots can be referenced in downstream models the same way as referencing models — by using the [ref](/reference/dbt-jinja-functions/ref) function.

Expand Down Expand Up @@ -417,12 +424,14 @@ Basically – keep your query as simple as possible! Some reasonable exceptions

Snapshot <Term id="table">tables</Term> will be created as a clone of your source dataset, plus some additional meta-fields*.

Starting in 1.9 or with [dbt Cloud Versionless](/docs/dbt-versions/upgrade-dbt-version-in-cloud#versionless), these column names can be customized to your team or organizational conventions via the [`snapshot_meta_column_names`](/reference/resource-configs/snapshot_meta_column_names) config.
Starting in 1.9 or with [dbt Cloud Versionless](/docs/dbt-versions/upgrade-dbt-version-in-cloud#versionless):
- These column names can be customized to your team or organizational conventions using the [`snapshot_meta_column_names`](/reference/resource-configs/snapshot_meta_column_names) config.
- Use the [`dbt_valid_to_current`](/reference/resource-configs/dbt_valid_to_current) config to set a custom future date for `dbt_valid_to` in new snapshot columns. When set, dbt will use this specified value instead of `NULL` for `dbt_valid_to` in the snapshot table.

| Field | Meaning | Usage |
| -------------- | ------- | ----- |
| dbt_valid_from | The timestamp when this snapshot row was first inserted | This column can be used to order the different "versions" of a record. |
| dbt_valid_to | The timestamp when this row became invalidated. | The most recent snapshot record will have `dbt_valid_to` set to `null`. |
| dbt_valid_to | The timestamp when this row became invalidated. <br /> For current records, this is `NULL` by default <VersionBlock firstVersion="1.9"> or the value specified in `dbt_valid_to_current`.</VersionBlock> | The most recent snapshot record will have `dbt_valid_to` set to `NULL` <VersionBlock firstVersion="1.9"> or the specified value. </VersionBlock> |
| dbt_scd_id | A unique key generated for each snapshotted record. | This is used internally by dbt |
| dbt_updated_at | The updated_at timestamp of the source record when this snapshot row was inserted. | This is used internally by dbt |

Expand Down
4 changes: 3 additions & 1 deletion website/docs/docs/dbt-versions/release-notes.md
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Expand Up @@ -42,7 +42,9 @@ Release notes are grouped by month for both multi-tenant and virtual private clo
- [Python SDK](https://docs.getdbt.com/docs/dbt-cloud-apis/sl-python) is now generally available

</Expandable>



- **New**: Use the [`dbt_valid_to_current`](/reference/resource-configs/dbt_valid_to_current) config to set a custom future date for `dbt_valid_to` in new snapshot columns. When set, dbt will use this specified value instead of `NULL` for `dbt_valid_to` in the snapshot table.
- **Behavior change:** [Multi-factor authentication](/docs/cloud/manage-access/mfa) is now enforced on all users who log in with username and password credentials.
- **Enhancement**: The dbt Semantic Layer JDBC now allows users to paginate `semantic_layer.metrics()` and `semantic_layer.dimensions()` for metrics and dimensions using `page_size` and `page_number` parameters. Refer to [Paginate metadata calls](/docs/dbt-cloud-apis/sl-jdbc#querying-the-api-for-metric-metadata) for more information.
- **Enhancement**: The dbt Semantic Layer JDBC now allows you to filter your metrics to include only those that contain a specific substring, using the `search` parameter. If no substring is provided, the query returns all metrics. Refer to [Fetch metrics by substring search](/docs/dbt-cloud-apis/sl-jdbc#querying-the-api-for-metric-metadata) for more information.
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96 changes: 96 additions & 0 deletions website/docs/reference/resource-configs/dbt_valid_to_current.md
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@@ -0,0 +1,96 @@
---
resource_types: [snapshots]
description: "Snapshot dbt_valid_to_current custom date"
datatype: "{<dictionary>}"
default_value: {"dbt_valid_from": "dbt_valid_from", "dbt_valid_to": "dbt_valid_to", "dbt_scd_id": "dbt_scd_id", "dbt_updated_at": "dbt_updated_at"}
id: "dbt_valid_to_current"
---

Available in 1.9 or with [Versionless](/docs/dbt-versions/upgrade-dbt-version-in-cloud#versionless) dbt Cloud.

<File name='snapshots/schema.yml'>

```yaml
snapshots:
my_project:
+dbt_valid_to_current: "to_date('9999-12-31')"

```

</File>

<File name='snapshots/<filename>.sql'>

```sql
{{
config(
unique_key='id',
strategy='timestamp',
updated_at='updated_at',
dbt_valid_to_current='to_date('9999-12-31')'
)
}}
```

</File>

<File name='dbt_project.yml'>

```yml
snapshots:
[<resource-path>](/reference/resource-configs/resource-path):
+dbt_valid_to_current: "to_date('9999-12-31')"
```

</File>

## Description

Use the `dbt_valid_to_current` config to set a custom future date for `dbt_valid_to` in new snapshot columns. When set, dbt will use this specified value instead of `NULL` for `dbt_valid_to` in the snapshot table.

This simplifies makes it easier to assign date, work in a join, and range-based filtering with an end date.

## Default

By default, `dbt_valid_to` is set to `NULL` for current (most recent) records in your snapshot table. This means that these records are still valid and have no defined end date.

If you prefer to use a specific value instead of `NULL` for `dbt_valid_to` in current and future records, you can use the `dbt_valid_to_current` configuration option. For example, setting a date in the far future, `9999-12-31`.

The value assigned to `dbt_valid_to_current` should be a string representing a valid date or timestamp, depending on your database's requirements. Use expressions that work within the data platform.

### Managing records
- For existing records &mdash; To avoid any unintentional data modification, dbt will _not_ automatically adjust the current value in the existing `dbt_valid_to` column. Existing current records will still have `dbt_valid_to` set to `NULL`.

- For new records &mdash; Any new records inserted after applying the `dbt_valid_to_current` configuration will have `dbt_valid_to` set to the specified value (for example, '9999-12-31'), instead of `NULL`.

This means your snapshot table will have current records with `dbt_valid_to` values of both `NULL` (from existing data) and the new specified value (from new data). If you'd rather have consistent `dbt_valid_to` values for current records, you can either manually update existing records in your snapshot table where `dbt_valid_to` is `NULL` to match your `dbt_valid_to_current` value or rebuild your snapshot table.

## Example

<File name='snapshots/schema.yml'>

```yaml
snapshots:
- name: my_snapshot
config:
strategy: timestamp
updated_at: updated_at
dbt_valid_to_current: "to_date('9999-12-31')"
columns:
- name: dbt_valid_from
description: The timestamp when the record became valid.
- name: dbt_valid_to
description: >
The timestamp when the record ceased to be valid. For current records,
this is either `NULL` or the value specified in `dbt_valid_to_current`
(like `'9999-12-31'`).
```

</File>

The resulting snapshot table contains the configured dbt_valid_to column value:

| id | dbt_scd_id | dbt_updated_at | dbt_valid_from | dbt_valid_to |
| -- | -------------------- | -------------------- | -------------------- | -------------------- |
| 1 | 60a1f1dbdf899a4dd... | 2024-10-02 ... | 2024-10-02 ... | 9999-12-31 ... |
| 2 | b1885d098f8bcff51... | 2024-10-02 ... | 2024-10-02 ... | 9999-12-31 ... |
1 change: 1 addition & 0 deletions website/sidebars.js
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Expand Up @@ -978,6 +978,7 @@ const sidebarSettings = {
"reference/resource-configs/updated_at",
"reference/resource-configs/invalidate_hard_deletes",
"reference/resource-configs/snapshot_meta_column_names",
"reference/resource-configs/dbt_valid_to_current",
],
},
{
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