Along with a name and description, each Data Class is defined by a set of attributes. For example, an Animal Subject Data Class might have attributes for ID#, age, sex, and genotype. This help page serves as a reference for various aspects of Data Class attributes.

Components of Attributes
Attribute Types
Available Widgets for Attributes
Widget Descriptions and Syntax

Components of Attributes

Each attribute consists of the following:

Component	Description	Example
Name (label)	The attribute name, or label, is the identifier for the attribute.	Age in years
System Name	The system name is an attribute identifier formatted following database rules and conventions. (This name actually corresponds to a database table column, however you will not need to know that unless you are building an Advanced Query). The system name is automatically generated by the system using the label you specify so you do not have to worry about this component.	age_in_years
Type	The type specifies what kind of data item the attribute will store. See the Attribute Types section below for more details about available types	Integer
Required	This value determines whether the attribute is required or not. If it is required, then when items are entered into the database, an error is given if no value is specified for this attribute.	yes - we want the age of a subject to be a required field
Unique	This value determines whether the attribute must specify a unique value for each item entered in the database. If it must be unique, then when an item is entered with a duplicate value for this attribute, an error is given.	no - multiple subjects can have the same age
Label	This value determines whether the attribute should be included in the label representing an item.	no - we do not want to show the age of a subject in a subject item's label. (We just want to show the subject's name)
Note	Any additional information you may want to provide to users when entering or viewing the value for this attribute.	"Enter age of subject at study start"
Edit Widget	The web form input field to provide in the web interface for users to enter the attribute value when adding a new item or editing an existing item. See the Available Widgets section below for details about the widgets available for each attribute Type	Edit box/text field
Query Widget	The web form input field to provide in the web interface for users to query for an item. See the Available Widgets section below for details about the widgets available for each attribute Type	Edit box/text field

Attribute Types

Type	Description	Example
Limited Length String	A string of characters with a max length. If this type is selected, the max length should be specified in the Max Length column (otherwise defaults to 20).	A drug name for a treatment under study
Unlimited Length String	A string of characters with an unlimited length.	A free text description of an experimental protocol
Integer	A integer	A subject's age in years
Decimal	A decimal	A subject's body temperature during exam
Date	A date	A subject's date of birth
Multiple Options	A set list of possible values of which multiple can be selected. If this type is selected, the list of possible values should be listed in the Option List column (one option per line)	Symptoms a subject may be experiencing
Single Option	A set list of possible values of which one can be selected. If this type is selected, the list of possible values should be listed in the Option List column (one option per line)	A subject's gender
User	A registered User of the system	The user who entered the exam results
File	A file (e.g. an image, Word document, spreadsheet, pdf, movie)	A gel electrophoresis image
URL	A web address	A link to a PubMed reference
<Data Class>	A reference to an item belonging to <Data Class> (for any Data Class defined for the current Data Store)	The treatment a subject is given

Available Widgets for Attributes

Type	Edit Widgets	Query Widgets
Limited Length String	text field text area password field	text field text area
Unlimited Length String	text field text area	text field text area
Integer	text field text area	2 text fields to specify range
Decimal	text field text area	2 text fields to specify range
Date	date field text field	date field text field
Multiple Options	scrolling list box (multiple) checkbox group	scrolling list box (multiple) checkbox group
Single Option	scrolling list box (single) popup menu radio group	scrolling list box (multiple) checkbox group
User	scrolling list box (single) popup menu radio group	scrolling list box (multiple) checkbox group
File	file field	text field
URL	text field	text field
<Data Class>	scrolling list box (single) popup menu radio group	scrolling list box (multiple) checkbox group

Widget Examples and Syntax

Attribute widgets for editing and querying items can be modified. The available widgets for each attribute type is listed above in the Available Widgets for Attributes section above. To modify which widgets are used in your graphical interfaces, see the Edit Data Classes section.

Widget	Example	Syntax
text field		textfield(<size>,<max num characters>)
text area	line one line two	textarea(<rows>,<columns>)
popup menu		popup_menu
scrolling list box		scrolling_list(<num rows>)
radio group	option 1 option 2	radio_group
checkbox group	option 1	checkbox_group
file field		filefield
date field		datefield
password field		password_field(<size>)