# Versioning
## Structure
The files are stored in `DATABASE/.versions/TAG/DATE` and the file contents are identical to the Record.
## Limit Versions
When initializing, add `limit:number` to the versioning object to limit the number of stored versions.
{% code lineNumbers="true" %}
```javascript
const db = new Dubnium('dir', 'txt', { versioning:{ enabled:true, limit:10 } })
```
{% endcode %}
## Read A Version
{% code lineNumbers="true" %}
```javascript
db.get('tag').getVersion('date')
```
{% endcode %}
| Parameter | About | Type | Required |
|---|
| tag | Record tag | String | true |
| date | Date of version | String (ISO date) | true |
## Manually Save Snapshot
{% hint style="info" %}
This allows you to create a version at any point in time, even if automatic versioning is disabled or the limit has been reached.
{% endhint %}
{% code lineNumbers="true" %}
```javascript
db.get('tag').saveSnapshot()
```
{% endcode %}
### Example
{% code lineNumbers="true" %}
```javascript
await db.create('snapshot_test', { value: 'snapshot' });
const { timestamp, record:snapshotRecord } = await db.get('snapshot_test').saveSnapshot();
const snapshotData = await db.get('snapshot_test').getVersion(timestamp);
assert.equal(snapshotData, (await snapshotRecord.read(true)), 'Snapshot data mismatch');
```
{% endcode %}
## Generator
{% code lineNumbers="true" %}
```javascript
for (const version of db.get('tag').versions()) {
const { timestamp, record } = version
}
```
{% endcode %}
## Rollback
{% code lineNumbers="true" %}
```javascript
db.get('tag').rollback('date?')
```
{% endcode %}
| Parameter | About | Type | Required |
|---|
| tag | Record tag | String | true |
| date | Date of version | String (ISO date) | false |