Supporting Components

Association Name (association_name)

The identifier of the association to extend. This must be an entity name of a previously defined association. When referencing a core association in an extension project, the namespace "EdFi." must be included before the association name. 

Association Property

Defines a property referencing an association for the containing entity. The association name should be the name of an existing entity. When referencing an association defined outside of the current extension project, the namespace reference must be included before the association name. If the containing entity defines more than one property of the same entity type, the <role_name> syntax should be used to differentiate between the properties. This syntax can also be used to add contextual information about the reference. The property can be defined as weak to avoid creating foreign keys during ODS generation.

Base Association Name (base_association_name)

The identifier of the association to subclass. This must be an entity name of a previously defined association.

Base Domain Entity Name (base_domain_entity_name)

The identifier of the domain entity to subclass. This must be an entity name of a previously defined domain entity.

Boolean Property

Defines a boolean property for the containing entity. It is recommended to not use the cardinality of is optional in order to avoid turning this property into a tertiary value.

Cardinality

Cardinality is applied to properties to indicate the multiplicity of the property to the containing entity.

* If this cardinality is applied to a common type property, the ODS generation will result in a dependent table.

Choice Property

Defines a property referencing a choice entity for the containing entity. Choice entity name should be the name of an existing choice entity. When referencing a choice entity defined outside of the current extension project, the namespace reference must be included before the choice entity name. If the containing entity defines more than one property of the same choice entity, the <role_name> syntax should be used to differentiate between the properties.

Common Entity Name (common_entity_name)

The identifier of the common entity to subclass. This must be an entity name of a previously defined common.

Common Property

Defines a property referencing a common entity for the containing entity. Common entity name should be the name of an existing common entity. When referencing a common entity defined outside of the current extension project, the namespace reference must be included before the common entity name. If the containing entity defines more than one property of the same common type, the <role_name> syntax should be used to differentiate between the properties.

The extension keyword modifier may be used in a top level extension entity (e.g. Domain Entity Extension) to declare an override of a common property in the base entity. This requires that there be a corresponding extension of the common entity referenced by the common property in the base entity. The extended entity will then have the original common entity substituted with the extended common entity. The base entity remains unchanged. 

Currency Property

Defines a currency property for the containing entity. The XSD defines this type as a decimal with no other restrictions. The ODS generation creates a database field of type money.

Date Property

Defines a date property for the containing entity. 

Datetime Property

Defines a datetime property for the containing entity. 

Decimal Property

Defines a decimal property for the containing entity.

Descriptor Property

Defines a property referencing a descriptor entity for the containing entity. Descriptor name should be the name of an existing descriptor type. When referencing a descriptor defined outside of the current extension project, the namespace reference must be included before the descriptor name. If the containing entity defines more than one descriptor property of the same type, the <role_name> syntax should be used to differentiate between the properties. This syntax can also be used to add contextual information about the descriptor.

Deprecated (deprecated and property_deprecated)

Indicates that this top level entity or property is planned for removal in a future model version. deprecated is followed by a text explanation of the deprecation reason.

Documentation (documentation)

All documentation must begin with the keyword documentation, followed by either the documentation text enclosed in double quotes or the keyword inherited. Whitespace and line breaks are preserved within the double quotes. Because the double quote character denotes the beginning and ending of the documentation text, any double quote characters in the text itself are denoted by a consecutive pairing of double quotes. There is no maximum length for documentation text. Alternatively, properties that refer to other entities may use the inherited keyword to use the documentation of that entity.

Domain Entity Name (domain_entity_name)

The identifier of the domain entity to include in the association. This must be an entity name of a previously defined domain entity.

Domain Entity Property

Defines a property referencing a domain entity for the containing entity. The domain entity name should be the name of an existing entity. When referencing a domain entity defined outside of the current extension project, the namespace reference must be included before the domain entity name. If the containing entity defines more than one property of the same entity type, the <role_name> syntax should be used to differentiate between the properties. This syntax can also be used to add contextual information about the reference. The property can be defined as weak to avoid creating foreign keys during ODS generation.

Domain Item (domain_item)

Domain items define the items that are part of a given domain or subdomain. The domain entity name or association name should be the name of the existing domain entity or association type. When referencing a domain entity or association defined outside of the current extension project, the namespace reference must be included before the domain entity or association name. 

Duration Property

Defines a property for the containing entity representing a time duration value. When referencing a property defined outside of the current extension project, the namespace reference must be included before the property name. The XSD generation uses the xsd:duration type while the ODS generation represents this data as an nvarchar(30).

Entity Name (entity_name)

The identifier for the entity. Entity names must begin with a capital letter and then contain numbers, upper case letters, and/or lower case letters.

Enumeration Property

Defines a property referencing an enumeration entity for the containing entity. Enumeration name should be the name of an existing enumeration type. When referencing an enumeration defined outside of the current extension project, the namespace reference must be included before the enumeration name. If the containing entity defines more than one enumeration property of the same type, the <role_name> syntax should be used to differentiate between the properties. This syntax can also be used to add contextual information about the enumeration.

Inline Common Property

Defines a property referencing an inline common entity for the containing entity. Inline common entity name should be the name of an existing inline common entity.

Inline commons may not be used in extension projects, but remain a feature of the core Ed-Fi namespace. 

When referencing an inline common entity defined outside of the current namespace, the namespace reference must be included before the inline common entity name. If the containing entity defines more than one property of the same inline common type, the <role_name> syntax should be used to differentiate between the properties.

Integer Property

Defines an integer property for the containing entity. To set the max value equivalent to SQL bigint , use keyword "big".

Interchange Element

Interchange elements define the type of data that can be submitted in a given interchange. The domain entity name or association name should be the name of the existing domain entity or association type. When referencing a domain entity or association defined outside of the current extension project, the namespace reference must be included before the domain entity or association name. 

Interchange Identity Template

Interchange identity templates define a way to reference external domain entities or associations from an interchange. The domain entity name or association name should be the name of the existing domain entity or association type. When referencing a domain entity or association defined outside of the current extension project, the namespace reference must be included before the domain entity or association name. An identity template is not persisted to the ODS when submitted in an interchange. It only provides an XML shortcut for the interchange to reduce the amount of XML that must be transmitted.

Interchange Name (interchange_name)

The identifier of the interchange to subclass. This must be an entity name of a previously defined interchange.

Item

Items must specify a short description which is parsed as the remaining text on the line beginning with the item keyword. An item can optionally contain documentation.

Line Comment

Comments can be added to MetaEd code on a per-line basis. The comment indicator must be the first non-whitespace characters on the line. This causes the line to be ignored by the compiler.

Local Name (local_name)

The identifier for the shared property on the enclosing entity, which may be different from the name of the common simple type. Like regular property names, local names must begin with a capital letter and then contain numbers, upper case letters, and/or lower case letters.

Merge Directive (merge_part_of_reference)

Indicates that part of the reference should be merged with some portion of another reference on the same entity. Used for defining references to a common parent, primarily to support ODS generation. Can be used to merge part of a reference with an entire other reference property. User must build the path to map between the two.

A merge is defined by declaring a source and target property path for the merge. The first property path is the source, the second is the target. The following rules apply when defining merges:

1. All references must be a dot delimited path to the targeted reference.
2. All portions of the reference path must use the property name with the role name. For example, "ObjectiveGradeLevel", not just "GradeLevel".
3. All portions of the reference path should use the MetaEd name, not the derived artifact names. For example, "AcademicSubject", not "AcademicSubjectDescriptor".
4. The first part of the source path must be the parent property name.
5. The source reference path may resolve to any non collection property on the current entity, or any non collection identity property on a reference path.
6. The target reference path may resolve to any non collection identity property.
7. If the source is through a collection or common property, the target must be an identity property for the current entity.

MetaEdId (meta_ed_id)

Globally unique identifier for some element of the MetaEd language. Used by the Ed-Fi Alliance to identify elements, particularly for managing change tracking between versions. Should be an unsigned integer, surround by square brackets ([ ]).

MetaEdIds are used by the Alliance. They're not required for Extension projects but can be used. Note, however, that the Alliance currently has no formal assignment of IDs or ID ranges for licensees, so implementers using IDs for Extensions should be aware that the IDs may need to change in the future.

Percent Property

Defines a percent property for the containing entity. The expected percent value is defined as a part per one hundred. The XSD restricts this value to a decimal between 0 and 1 with 4 decimal places. The ODS generation defines a field of type decimal(5,4).

Potentially Logical (potentially_logical)

Indicates that this reference may have a logical rather that literal interpretation in a target technology. For example, applications may have an identifier for the target of a reference, but there is no way for the application to convert this to a literal reference that directly references an actual entity. This keyword indicates that only a logical relationship may exist. The implementation of this may be technology dependent, or may be defined by downstream specifications.

Property Name (property_name)

The identifier for the property. Property names must begin with a capital letter and then contain numbers, upper case letters, and/or lower case letters.

Property

There are many different types of properties that can be defined. Each syntax label specifies the expected syntax for the given property type.

Queryable

Indicates that the property is part of an XSD lookup type for that entity. The is queryable field modifier is optional after the cardinality indicator. Alternatively, a queryable property may be declared for an entity where that property is not on the entity itself but instead accessible through an Association. In this case, the is queryable only modifier replaces the cardinality indicator.

Role Name and Shorten To

The role name keywords are used to add additional terms to the generated name of a specified property. The role name is appended to the beginning of the descriptor, domain entity or enumeration name when the XSD and ODS generation is run to build the name of the XSD element or database field. This syntax can be used to give different names to properties of the same type within the same entity. It can also be used to provide more contextual information about the data being collected in the given property. Artifacts may generate differently when a role name is the same as the property name. For example, XSD generation ignores the role name in this case.

The optional modifier shorten to  can be used to fully rename the property. Again, artifact generation naming may behave differently. For example, XSD generation will ignore the rename and use only the role name.

Short Description (short_description)

The text of the enumeration value. This can be a single word or phrase. It is limited to a single line of text.

Shared Property

Defines a property referencing a shared simple type for the containing entity. The shared simple type name should be the name of an existing entity. When referencing a shared simple type defined outside of the current extension project, the namespace reference must be included before the shared simple type name. The local name specified after the named keyword is optional, and provides a different property name to be used on the containing entity.

Shared Simple Type Name (shared_simple_type_name)

The identifier of the shared simple type to include in the enclosing entity. This must be an entity name of a previously defined shared simple type.

Short Property

Defines a short property for the containing entity. The output property will automatically have a maximum value that is smaller than an int  property, equivalent to SQL's smallint  data type. 

String Property

Defines a string property for the containing entity.

Subdomain Position (subdomain_position)

The position of the subdomain relative to other subdomains in the domain. Used to order the subdomains when showing them together. Must be an unsigned integer.

Time Property

Defines a time property for the containing entity.

Year Property

Defines a year property for the containing entity. The XSD generation defines this as a xsd:gYear type while the ODS generation creates a field of type smallint.