When two features are merged, an attribute's value is controlled by its merge policy.Įach attribute domain has both a split policy and a merge policy. The behavior of an attribute's values when a feature is split is controlled by its split policy. While the results of these types of edit operations on the feature's geometry are easily predictable, their effects on the attribute values are not. Similar zoning changes may require two adjacent parcels to be merged into a single parcel. For example, in a landbase database, a land parcel may be split into two separate land parcels due to rezoning. Often, when editing data, a single feature is split into two features or two separate features are combined, or merged, into a single feature. Validation for coded value domains is accomplished by restricting the user to choose field values from a drop-down list. The coded value domain includes both the actual value that is stored in the database (for example, 1 for pavement) and a more user-friendly description of what that value actually means. Coded value domains specify a valid set of values for an attribute.įor example, water mains may be buried under different types of surfaces as signified by a GroundSurfaceType attribute field: pavement, gravel, sand, or none (for exposed water mains). Coded domains-A coded value domain can apply to any type of attribute-text, numeric, date, and so on.Learn more about Editing with default values and attribute domains. Range domains are validated through the use of the Validate Features command. For a distribution water main object to be valid, its pressure value must be entered as some value between 50 and 75 psi. Distribution water mains can have a pressure between 50 and 75 psi. A range domain can be applied to short-integer, long-integer, float, double, and date attribute types.įor example, in a feature class for water mains, you could have subtypes for transmission, distribution, and bypass water mains. When creating a range domain, you enter a minimum and maximum valid value. Range domains-A range domain specifies a valid range of values for a numeric attribute.There are two types of attribute domains: When you create a domain, you must specify which type of domain you want to use. Once the field type is set, the name of the domain will appear in the domain drop-down list for any field of that type in the Properties dialog box. Text (Coded domains only)-Alphanumeric characters. Double-Double-precision floating point numbers.Float-Single-precision floating point numbers.The field type can be set to any of the following: The field type is the type of attribute field with which the domain can be associated. The description is a small sentence describing the purpose of the domain. The characters ' and `, a single quote and an apostrophe, may not be used when naming a domain.Īfter a domain is created, when you open the Properties dialog box for a feature class or table, the domain name is displayed in the domain drop-down menu when choosing a domain to associate with a given field. When creating a new domain, you specify a name that will describe the parameter it governs. When creating or modifying a domain, you must edit the following properties: Name and description Using domains helps ensure data integrity by limiting the choice of values for a particular field.Īttribute domains can be shared across feature classes, tables, and subtypes in a geodatabase.įor example, a feature class for water mains and a feature class that stores water laterals can use the same domain for the ground surface type field. In other words, the field will not accept a value that is not in that domain. Whenever a domain is associated with an attribute field, only the values within that domain are valid for the field. A domain is a declaration of acceptable attribute values. If the features in a feature class or nonspatial objects in a table have been grouped into subtypes, different attribute domains can be assigned to each of the subtypes. Attribute domains are used to constrain the values allowed in any particular attribute for a table or feature class. Attribute domains are rules that describe the legal values of a field type, providing a method for enforcing data integrity.
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