Data migration (Maritime Charting)

When producing nautical charts, you collect each individual chart in its own geodatabase. Depending on your library, you might have to join these individual charts together. You may also need to reproduce only one chart in a multiple chart library. This could require two geodatabases: one for production and a second for maintenance. Depending on your situation, you may need to migrate your data into a single geodatabase before you can edgematch it.

Edgematching

You can adjust data from several sources before it is imported into the master database. The spatial adjustment tools let you rubbersheet and edgematch features in your map from different layers. It is always a good idea to use quality-control tools again after you edgematch your data.

With the data in one library geodatabase, it is easy to quickly adjust features along Dqyarea edges. The main things to consider during this process are symbolizing data in a meaningful way and the snapping environment.

Symbolizing the data

During edgematching, it is more efficient to identify the attributes of the features being snapped. The easiest way to identify where the attributes match between features is to symbolize or label them in a meaningful way. A quick way to symbolize the data is to use the DNCH.mxd, DNCA.mxd, DNCC.mxd, or DNCG.mxd templates.

提示:

Make a copy to avoid altering the template DNC<scale>.mxd files.

Snapping

Snapping settings are located on the Snapping toolbar. When snapping is turned on, your pointer will jump, or snap to, edges, vertices, and other geometric elements when your pointer is near them and within a certain tolerance. This enables you to position a feature easily in relation to the locations of other features.

Editing topology

Many features have topological relationships that need to be maintained (for example, Hydline and Hydarea). A way to easily maintain these relationships during edgematching is to use the topology editing tools. For example, these tools allow you to move or reshape the coastline and all associated features (including the open water, ground surface elements, depth curve areas, and any other feature with shared geometry).

General edgematching tips

When edgematching a feature class, it is important to maintain relationships between features. During edgematching, relationships can be destroyed when features are moved.

The goal is to create a seamless representation of the library data. When resolving discrepancies, follow these guidelines:

• Move small-scale data to large-scale data if the adjoining charts have different scales.
• New editions take precedence over older editions.
• If both sources have the same edition and the same scale, split the difference.
• Always use feathering when moving one arc to meet another. This avoids sharp angles.
• Always ensure that you maintain coincidence between features.
• When you merge or unsplit features, only one feature's GFID is preserved. If that remaining feature has a note that is no longer valid, you must use the Notes Editor to attach the correct note.

Feature class edgematching tips

Certain feature classes have specific considerations for edgematching.

Dqyarea

Do not dissolve the boundaries between these features.

Ecrtext

Delete duplicate annotation that occurs across Dqyarea boundaries.

Hydarea

• When dissolving boundaries, only join areas with the same closing band.
• If two areas have the same closing band but one area is ACC = 1 and the other is ACC = 2, the ACC = 2 area takes precedence.
• When edgematching areas with CVL or CVH values associated with soundings, always update to the area with the shallowest or deepest value.
• When moving depth areas, make sure you do not place sounding points on the wrong side of the area.

Hydline

When moving depth curves, make sure you do not place a sounding point on the wrong side of the curve.

General obstructions (wrecks, rocks)

When edgematching these area features, their attribute codes might differ slightly. Merge these features with the most hazardous combination taking precedence; for example, one feature has TXT = Rock and another feature has TXT = Rocks. The feature with TXT = Rocks takes precedence since multiple rocks are more hazardous.

Point feature classes

Check all point feature classes for duplicate points along the Dqyarea boundary. This could also apply for all line and area feature classes.

Make sure that no point features are misplaced when moving line or area features.

Migrating your geodatabase

The first step for edgematching is to combine all the chart datasets into one master library geodatabase using Data Loader. Data Loader allows data to be copied from one geodatabase and appended to an existing geodatabase. A mapping template is used to map one feature class to another between the geodatabases. You can find the template files in the following folders:

• 32-bit Windows operating systems—<Installation location>\Program Files\ArcGIS\MaritimeCharting\Desktop10.2.2\Dnc\DataConversion
• 64-bit Windows operating systems—<Installation location>\Program Files(x86)ArcGIS\MaritimeCharting\Desktop10.2.2\Dnc\DataConversion

This template contains a mapping file that maps the source's feature class to the destination's feature class.

Many libraries are made up of multiple charts. Typically, these charts are collected individually from each other and, once complete, joined together to make the final library geodatabase. To create an output database, you can use one of the following methods and then use the Data Loader tool on the Production Mapping toolbar in ArcCatalog to migrate all your data:

• Start with an empty output geodatabase and load all the data into it.
• Start with a copy of one of the geodatabases to be joined as the output geodatabase and append the rest of the data to it.

Once you have migrated your data, you need to migrate your note tables.

Migrating your note tables

When loading DNC data from one geodatabase to another, the features themselves are loaded, while any notes.rat tables are left behind in the source geodatabase. These notes need to be loaded into the target geodatabase and reattached to their respective features. This is done through the Notes Migration tool found on the Nautical DNC toolbar in ArcCatalog.

The migration actually appends to existing note tables in the destination geodatabase. Since all the notes are linked by the GFID and the GFID is unique for all features produced by ArcGIS for Maritime:Charting, the notes will automatically be referenced in the new geodatabase. This is because the note join table contains the GFID of each feature that has a note.