Editing Template:EPrints Metadata Fields Content (section)

== Inheritance ==

This is the list of ''useful'' field types. Under it is listed the other field types which are just included for completeness and are not intended to be used as part of the configuration.

Some field types inherit the properties of another, and then modify them in some way. For example the [[namedset field]] works like a [[set field]] except that it gets its options from a namedsets file not from the options=>[] in the field properties.

* '''Basic metadata field''' - this is abstract, fields must be one of the types listed below...
** '''[[Boolean field|Boolean]]''' - TRUE or FALSE (or can be unset, of course).
** '''[[Compound field|Compound]]''' - virtual field, joins together several "multiple" fields, e.g. author_name and author_email.
*** '''[[Dataobjref field|Dataobjref]]''' - references another data object.
*** '''[[Multilang field|Multilang]]''' - allows language variants of a field, e.g. titles in French, German and/or English.
*** '''[[Relation field|Relation]]''' - stores a typed relationship with something represented by a URI.
** '''[[Date field|Date]]''' - stores a date
*** '''[[Time field|Time]]''' - stores a date and time
**** '''[[Timestamp field|Timestamp]]''' - stores current date and time
** '''[[Float field|Float]]''' - stores a floating-point value
*** '''[[Decimal field|Decimal]]''' - stores a decimal number.  Specifying the length of number before and after the decimal point.
** '''[[Id field|Id]]''' - like basic text field but search only finds exact matches
*** '''[[Idci field|Id (case-insensive)]]''' - like Id field but search find exact matches ignoring case (use for usernames, email addresses, etc.)
**** '''[[Email field|Email]]''' - an email address
*** '''[[Keywords field|Keywords]]''' - stores as longtext but searchable as exact individual keyword phrases
*** '''[[Recaptcha field|Recaptcha]]''' - virtual field to display a reCAPTCHA to prevent spamming of public input forms.
*** '''[[Text field|Text]]''' - the basic text field. Maximum 255 bytes. nb. uft-8 means some chars take more than one byte.
**** '''[[Longtext field|Longtext]]''' - like text but allows much longer text (65,000 bytes).
***** '''[[Longtext_counter field|Longtext counter]]''' - like longtext but with a word counter (requires [https://jquery.com/download/ jQuery])
**** '''[[Pagerange field|Pagerange]]''' - a range of page from one number to another.
**** '''[[Secret field|Secret]]''' - used to store passwords and other secrets.
**** '''[[Set field|Set]]''' - a limited set of options
***** '''[[Namedset field|Namedset]]''' - like a normal set, but takes its options from a [[namedset]] configuration file.
***** '''[[Subject field|Subject]]''' - possible values are taken from the [[Subject Object|Subject]] hierarchy. 
***** '''[[Base64 field|Base64]]''' - stores Base64 encoded data.
****** '''[[Image field|Image]]''' - stores image encoded in Base64 data.
*** '''[[Url field|Url]]''' - stores a URL.
*** '''[[Uuid field|Uuid]]''' - stores a UUID.
** '''[[Int field|Int]]''' - an integer value
*** '''[[Bigint field|Bigint]]''' - a large integer value (can be greater than 2,147,483,647 or less than -2,147,483.647).
*** '''[[Counter field|Counter]]''' - an auto-incrementing integer value.
*** '''[[Itemref field|Itemref]]''' - a reference to another [[Data Object]] (e.g. a user or other eprint)
*** '''[[Pagerange field|Pagerange]]''' - a pagerange, e.g. 122-130
** '''[[Multipart field|Multipart]]''' - Stores a mutiple sub-fields like a person's name.
*** '''[[Name field|Name]]''' - Stores a person's name broken up into logical parts.
** '''[[Subobject field|Subobject]]''' - Stores another data object under a parent data object.

=== Internal-use and Deprecated Field Types ===
* '''Basic metadata field'''
** '''[[File field|File]]''' - '''DEPRECATED'''.  Use [[Subobject field]] instead.
** '''Id''' 
*** '''Text'''
**** '''Set'''
***** '''[[Arclanguage field|Arclanguage]]''' - as for set, but the options are the valid languages of this repository.  Probably better to use [[Multilang field]].
***** '''[[Fields field|Fields]]''' - as for set, but the options are the fields in a dataset.
***** '''[[Langid field|Langid]]''' - used internally by [[Multilang field]]s to store the language ID.
**** '''Longtext'''
***** '''[[Search field|Search]]''' - a serialised search 
** '''Int'''
*** '''[[Year field|Year]]''' - '''DEPRECATED'''.  Use [[Date field]] instead.
** '''[[Storable field|Storable]]''' - Stores a serialization of a Perl data structure.