# Point record changes: effects on other points

The Trimble Access software uses a dynamic database. If you change the name or coordinates of a record, the positions of other records that rely on that record could change or disappear. Deleting a record can result in null coordinates for records that rely on the deleted record.

If you select a range of records and change their name, all the selected records are renamed to the new name that you entered.

If you rename or edit the coordinates of points, all records that contain computed deltas to other points, for example as‑staked, check, and backsight observations, are not updated.

Base station or station setup positions

If you rename a point name that is used as a base in a GNSS survey, or as a station setup point in a conventional survey, this does not rename the point name that is referenced in the Base record or Station setup record. You cannot edit the point name referenced in the Base record or Station setup record.

If you rename the base position or station setup position, and another record with the same name

- does not exist, then the positions of all records that are computed from that base position or station setup position cannot be computed, and those records will no longer be displayed in the map.
- does exist, then the positions of all records that are computed from that base position or station setup position may change, as they will be computed from the next best point with the same name.

If you edit the base position or station setup position, then the positions of all records that are computed from that base position or station setup position will change.

If you edit the azimuth in an a station setup with a keyed‑in azimuth to the backsight, then the positions of all records that are computed from that station setup will change.

Backsight positions

If you edit or rename the point record that is used as a backsight in a station setup with a computed azimuth to the backsight, then the positions of all records that are computed from that station setup may change.

Changes to other positions

Changes to resections, lines, arcs, compute inverse records, and others may also affect other positions. Refer to the table below, where the * symbol shows the database records that may change if the name or the coordinates of the record that was used to derive their position is modified.

Record | Names | Coordinates
--- | --- | ---
Topo points (GNSS) | * | *
Rapid points | * | *
FastStatic points | * | *
Observed control points | * | *
Face 1 Topo points (Conv.) | * | *
Face 2 Topo points (Conv.) | * | *
Mean turned angle | * | *
As‑staked points | * | *
Check points | * | *
Continuous points | * | *
Construction points | * | *
Laser points | * | *
Lines | * | *
Arcs | * | *
Compute inverse | * | *
Resection points | – | –
Adjusted points | – | –
Averaged points | – | –
Cogo points (computed) (see note below) | * 1 | * 1
Intersection points | – | –
Offset points | – | –
Roads | – | –
Alignments | – | –
Tunnels | – | –
Calibration points | – | –
Compute area | – | –

1 – Cogo points can change if the point they are computed from is modified, but it depends on how the Cogo points were stored. If they were stored as a vector, for example Az HD VD and the base point is moved, then the Cogo point will also move.

Deleted items

A deleted point, line, arc, or polyline is not used in calculations, but it is still in the database. Deleting points, lines, arcs, or polylines does not make a job file smaller.

Some points, such as continuous offset points and some intersection and offset points, are stored as vectors from a source point. If you delete a source point, any point stored as a vector from that point has null (?) coordinates when you review the database point record.

When you delete an observation that has been recorded during a Station setup plus, a Resection, or Measure rounds operation, the mean turned angle records and station or round residuals records will not be updated. Deleting an observation that has been used to compute an average does not automatically update the average. Use COGO / Compute average to recompute the average.

You cannot delete points from a linked file.

Use File Explorer to delete alignment files, road files, map files, or any other file type stored on the controller.