Schema Editor

Use the Schema Editor to view or change settings for an entire schema hierarchy: schemas, feature classes, and properties.

You cannot control every aspect of a schema from the Schema Editor. For example, you cannot create object or association properties, or specify that the system auto-generate a value for a property. However, if you have set up these attributes for a schema, the Schema Editor will display the current settings.

The settings you see depend on what the provider supports. For example, Long Transactions will not appear if the provider doesn’t support versioning.

Import Schema

Import an XML schema that you exported, and use it to define a new schema for another data store. This is useful for creating multiple data stores based on the same schema

Export Schema

Export the selected schema as an XML file to share a schema you created in the Schema Editor with other AutoCAD Map 3D toolset or GIS-software users; to back up a schema you created in the Schema Editor as an XML file; or to save your work in progress if the original data source or directory becomes unavailable.

New Schema

Define a new schema in a new or existing feature source for a database FDO provider (Microsoft SQL Server, MySQL, or Oracle) or for an SDF data store. You cannot create a schema for an existing SHP feature source, but you can create a new file-based data store and create a new schema for it during the creation process.

New Feature Class

Select a schema entry on the right and click New Feature Class, and specify the information for the new feature class on the left side of the window.

New Property

Select the feature class entry for the property on the right and click New Property. Specify the information for the property on the left side of the window.

Schema Settings

Enter A Schema Name

Enter the name that will appear in the Schema tree. It must follow the naming rules of the provider.

Note:

You cannot change the schema name for a SQLite data store. The schema name must be “Default.” Also, for SQLite schemas, you cannot add comments in the Schema or Feature Class Description fields.

Description

Enter an optional description of the schema.

Feature Class Settings

Name

Enter the feature class name that will appear in the Schema tree. It must follow the naming rules of the provider.

Description

Enter an optional description of the feature class.

Type

Select Feature Class for a class with associated geometry. Select Non-feature Class for non-spatial data that can be used as a standalone or contained class.

For most providers, a feature class requires a unique identifier to distinguish it from other features (unless the feature class has a base class from which it inherits an identifier).

A non-feature class has no association with another class and requires a unique identifier. As a contained class, it defines a property of another non-feature or feature class. For example, Sidewalk could be a property of a Road feature class; the Sidewalk class defines the Road.Sidewalk property. In this case, the Sidewalk class does not need an identity property, although it could have one.

Base Feature Class

If this feature class inherits from another feature class, select that superclass; otherwise select None. This setting applies only to feature classes (not non-feature classes) and is available only if the provider supports inheritance.

Abstract

Click Yes if this feature class is an abstract class. You can’t create features for an abstract class, but you can use it as a base class. This setting applies only to features classes (not non-feature classes) and is available only if the provider supports inheritance.

Specify Identifier Propert(ies) And The Order

Select the properties that comprise the unique identifier (for non-null primary-key values) for this feature class. Select one property for a simple identifier or multiple properties for a compound identifier. (Some providers support only simple identifiers). Create these properties before you create any others. Use the arrow buttons to reorder the properties.

You must specify a value for any non-null property of a feature before you check that feature into the data store. If you do not, you will not be able to check the feature in.

Ordinarily, identifier properties use an auto-generated integer. This means that when you add new features to this feature class, they automatically receive an auto-generated, unique identifier. If you do not specify an auto-generated integer for this property, you must manually enter a unique identifier for each new feature that uses it.

Specify Unique Constraint(s) And The Order

Specify the criteria features must meet in order to be added to this feature class. Enter a constraint for this feature class in the Constraints box and click New to apply it. Create additional constraints if necessary. Use the arrow buttons to reorder the constraints. To remove a constraint, select it and click Delete. This setting is available only if the provider supports constraints. Constraint syntax is provider-specific.

Locking

Specify whether the user who checks out a feature controls that feature to the exclusion of other users, until it is checked back in. This setting applies only to providers that support locking.

Long Transaction

Specify whether to enable long transactions. A long transaction groups conditional changes to one or many features. Long transactions create different versions of a feature or set of features. This setting applies only to providers that support versioning.

Property settings

Name

Enter the name of the property that will appear in the Schema tree. It must follow the naming rules of the provider.

Each property is a single attribute of a feature class. For example, a Road feature class may have properties called Name, DateConstructed, and Location.

Type

Select Data for non-spatial data. Select Geometry for a property that defines an object’s shape.

A Data property data type is either boolean, byte, date/time, decimal, single, double, Int16, Int32, Int64, or string. For example, a Road feature can have a data property called DateConstructed whose data type is date/time.

The default Geometry property specifies one of four shapes: point (0 dimensions), curve/line (1 dimension), surface/polygon (2 dimensions), and solid (3 dimensions). A feature class has one main geometry property, but can have additional geometry properties. A geometry property is associated with a spatial context. All instances of a geometric property must have the same ordinate dimension. Not all providers support all geometry types or all dimensionalities; SHP supports only XY points, for example, whereas Oracle supports XY, XYZ, XYZM, and XYM points. The default is XY. Additionally, it can have attributes that describe elevation and measure: HasElevation for Z and HasMeasure for M.

A feature class has one main geometry property, but can have additional geometry properties. A geometry property is associated with a spatial context. All instances of a geometric property must have the same ordinate dimension. Not all providers support all geometry types or all dimensionalities; SHP supports only XY points, for example, whereas Oracle supports XY, XYZ, XYZM, and XYM points. The default is XY. Additionally, it can have attributes that describe elevation and measure: HasElevation for Z and HasMeasure for M.

The association property may appear in the list, but it is not supported by AutoCAD Map 3D toolset. Choose this property type only if existing data uses it and you want to maintain that data after it is moved to a different data store.

Description

Enter an optional description of the property.

System Generated

You cannot set this option, which indicates the current setting for this property in an existing schema. Yes indicates that the system will auto-generate values for this property. Generally, identifier properties whose values identify each feature uniquely are auto-generated.

Data Attributes

Click an attribute name in the schema tree to display its description. If you can change or specify the value for a property, a down-arrow or a blinking cursor appears in its field and you can select or enter a value.

The list changes dynamically to show the different attributes that are available for the selected property type.

Note:
The following caveats apply to certain providers:
  • You can constrain the default length of a string property in a SQLite schema. However, AutoCAD Map 3D toolset will not generate an error if the constraints are violated. Such validation slows down the performance of the data store. For example, you can constrain a string field to 2 characters and enter 3 characters without producing an error message. AutoCAD Map 3D toolset maintains the constraint information so that, for example, bulk copying to another data provider will product the desired constraint.
  • You cannot make SQLite properties read-only.
  • The Decimal data type actually uses a Double data type. For this reason, many providers will not check the number of decimal places when the data is checked in.