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Cartegraph Campus

Split and Merge Integrated Data

Performing Edits in ArcMap

  • Split commands like Split and Cut Polygon create multiple features from a selected feature. One of the resulting features is the original record with its geometry changed.
  • Union and Intersect perform geometric operations on multiple features to create a new feature and leave the original features in place.
  • Merge combines multiple features into one feature. One of the original features is preserved with the new expanded geometry; the other features are deleted. Fields and libraries may be created to cache geodatabase data.

The table below summarizes the ArcMap actions and the effect on the Geodatabases and the Cartegraph records:

 

Action 

GIS Record

Cartegraph Record

Cartegraph Child Records (Tasks, Inspections)

SPLIT

 

On new record

New records created

Attributes copied from original

No child records copied over

On original record

Attributes kept, Geometry changed

Attributes kept, geometry changed

Child records remain unchanged

MERGE

Target record specified by user is kept; additional records are deleted.

On target record

Attributes kept, Geometry changed

Attributes kept, geometry changed

Child records remain unchanged

On original record(s)

Deleted

Deleted

Deleted

UNION/INTERSECT

Original records retained; new record created where geometry intersects.

On target record

New record created—no attributes copied over

New record created—no attributes populated

None

On original record(s)

Kept as is

Kept as is

Kept as is

 

Split Features in ArcMap

When you use the ArcMap editing tool to split one feature into two, ArcMap creates one new feature with all the same attributes as the original and assigns half the original spatial data to the original record and the rest to the new record.

When an associated feature such as the segment shown above is split, the related Cartegraph record is split, too. The original record stays as is except its geometry is reduced, and a new record is created with copies of all the original record’s data. The new record contains no child data, however (tasks or inspections).

As with any other edit session in ArcMap, changes are not committed to the Cartegraph database until you use the ArcMap Save Edits command.

Connectivity and Split Features

Cartegraph records may contain references to shared recordsets, which may prevent you from splitting one feature into many. This is especially true for users who have connected one type of asset to another. This connection is used mostly for Sewer, Water, and Storm assets, though many other assets can be connected.

For example, a sewer main has a pump attached to it. The sewer main has a field that connects it to a sewer pump. Cartegraph makes sure that the pumps and mains stay in sync by enforcing referential integrity, which makes sure that if Main 10179 is attached to Pump 500, then Pump 500 must be associated with Main 10179.  Pump 500 can only be attached to a single main.

When ArcMap splits the sewer main into two new records, all the existing Cartegraph data are copied for the new records, including for the pump data. Though two mains can use the same pump, one pump cannot be connected to more than one main. Referential Integrity prevents this transaction when ArcMap saves the edits and commits the data to the Cartegraph database. The error message below displays:

“A database error has occurred. The record could not be deleted because it is referenced in the following places: The ‘ID’ field with a value of ‘10179’ is referenced 1 times by the ‘$\Sewer Pumps\Main ID’ field.”

To accomplish the split, the user must use Cartegraph software to disconnect the assets. In this example, you would locate the sewer pump that references main 10179 and delete that reference. Once the assets are disconnected, the sewer main can be split in ArcMap.

Manually Adjust Cartegraph Data on Split

Some care must be exercised when the ArcMap Split functionality is used. The data that is copied may not be appropriate. You must manually ensure that data integrity is maintained.

Correct Measurements

When new features are created, the contents of the original asset are copied to the new features. When manually entered measurements such as length, width, and area are involved, these may not be accurate.

Length is not associated to the Geodatabase Shape_length attribute. When the feature is split in ArcMap, a new Cartegraph record is created with the same attributes as the original record. Though the geometry used to show this asset on the map is adjusted, the measurements in Cartegraph, which may be used for calculations, are the same as the original. In the example shown, each of the new records has a length of 200 yards, though the new records are 100 yards each. Users must manually correct the length measurement in Cartegraph.

Failure to adjust measurement values can result in incorrect condition calculations and incorrect costs for planned maintenance activities.

This adjustment needs to be made only if the measurement is used in a calculation and the measurement is not associated to a calculated Geodatabase attribute such as Shape_Length.

Merge

When two or more features are merged in ArcMap, the user chooses which feature’s attributes are kept, including the ID. The geometries of all features are combined, the other features are deleted in GIS, and the selected record gets the updated combined geometry while keeping its attributes intact. In Cartegraph, the child data for the selected record is kept, and all other child records are discarded.

Union

A new feature is created when using the Union and Intersect tools in ArcMap. This new feature contains only geometry. No attributes are copied. In Cartegraph, a new record is created without features or child records.

 

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