All datasets have pre-defined (and required)
base fields. These system fields are used internally to track things like creation and modification, as well as participant and time for integration with other study data.
Dataset System Fields
| System Column | Data Type | Description |
|---|
| DatasetId | int | A number that corresponds to a defined dataset. |
| ParticipantId | string | A user-assigned string that uniquely identifies each participant throughout the Study. |
| Created | date/time | A date/time value that indicates when a record was first created. If this time is not explicitly specified in the imported dataset, LabKey will set it to the date/time that the data file was inserted. |
| CreatedBy | int | An integer representing the user who created the record. |
| Modified | date/time | A date/time value that indicates when a record was last modified. If this time is not explicitly specified in the imported dataset, LabKey will set it to the date/time that the data file was last modified. |
| ModifiedBy | int | An integer representing the user who last modified the record. |
| SequenceNum | float | A number that corresponds to a defined visit within a Study. This is a floating-point number. In general, you can use a visit ID here, but keep in mind that it is possible for a single visit to correspond to a range of sequence numbers. |
| Date | date/time | The date associated with the record. Note this field is included in datasets for both timepoint and visit based studies. |
| VisitDate | date/time | The date that a visit occurred (only defined in visit-based studies). |
Hidden Fields
Lists and datasets also have the following
hidden fields. To see them, open
(Grid Views) > Customize Grid and check the box for
Show Hidden Fields.
Hidden Fields in Lists
| Name | Datatype | Description |
|---|
| Last Indexed | date/time | When this list was last indexed. |
| Key | int | The key field. |
| Entity Id | text | The unique identifier for the list itself. |
| Folder | object | The container where this list resides. |
Hidden Fields in Datasets
| Name | Datatype | Description |
|---|
| Lsid | text | The unique identifier for the dataset. |
| Participant Sequence Num | text | A concatenation of the participant ID and sequence num |
| Source Lsid | text | A unique identifier for this row. |
| DSRowId | long int | The row in the current dataset |
| Sequence Num | other | The sequence number for the visit |
| Dataset | text | The name of the dataset |
| Container | text/link | The folder containing the dataset |
| Visit Row Id | int | The id of the visit |
| Folder | text | The folder containing the dataset |
Note that there may be additional reserved fields in some circumstances. If you see an error indicating a field name is reserved, try using a variation (such as using "Site_ID" if "SiteID" is reserved). You can use a field label to show the "reserved" name in your grids if desired.
Related Topics
