Date field
EPrints 3 Reference: Directory Structure - Metadata Fields - Repository Configuration - XML Config Files - XML Export Format - EPrints data structure - Core API - Data Objects
Metadata Fields: Arclanguage - Base64 - Bigint - Boolean - Compound - Counter - Dataobjref - Date - Decimal - Email - Fields - Float - Id - Idci - Image - Int - Itemref - Keywords - Langid - Longtext - Longtext_counter - Multilang - Multipart - Name - Namedset - Pagerange - Recaptcha - Recaptcha3 - Relation - Search - Secret - Set - Storable - Subject - Subobject - Text - Time - Timestamp - Url - Uuid
Contents
Description
This field is used to store a single date. Internally EPrints always uses ISO standard notation for dates, it avoids confusion. This is YYYY-MM-DD.
In bibliographies sometimes exact dates of publication (or other events) are not known. EPrints allows you to store month and year values in date fields. YYYY or YYYY-MM.
In the database EPrints actually uses 3 integer fields to store the date, rather than a built in date field. This is because of the need to allow NULL in month and day if the date is just 1998.
Inheritance
Additional Properties
Name | Default | Required | Description | Notes |
---|---|---|---|---|
min_resolution | day | NO | The minimum resoltion of date that must be entered. Can be day, month or year. | If set to day then values of YYYY or YYYY-MM will cause a validation error. If set to month then values of YYYY will cause a validation error. If set to year then day, month or year resolutions are allowed. |
render_res | day | NO | The resolution to render the date stored by this field. Can be day, month or year. | If set to year then the dates 1998-10-01, 1998-10 and 1998 would all be rendered as 1998. This is not too useful in configuring the field, but can be set as a print option inside citation files. |
render_style | long | NO | The resolution to render the date stored by this field. Can be short, long ordow. | If long then you'll see 8 September 1998. If short then 08 Sep 1998. dow would render Tuesday 8 September 1998. |
Required Phrases
No additional phrases beyond the standard metadata field phrases.
Database
Date fields are stored in the database as:
fieldname_year SMALLINT(6) fieldname_month SMALLINT(6) fieldname_day SMALLINT(6)
If a date only has a year value then it would be stored as 1998,NULL,NULL
API
See API page.
Date values are represented in the API as scalars containing ISO encoded dates. eg.
"1976" "1976-02" "1976-02-02"
Searching
Date fields can be searched as either single values or ranges. Searching for 2006> will also match 2006-12-25. You can search for 2000- to search dates in or after 2000. Or 2000-12-2003-01 for December 2000 through January 2003.
Examples
Most basic example.
{ name => 'acceptance_date', type => 'date', }
Set minimum resolution to which the date must be specified is at least a month.
{ name => 'moratorium_date', type => 'date', min_resolution => 'month', }
Set resolution to render to the month, set rendering style to short (e.g. Feb 2023).
{ name => 'publication_date', type => 'date', render_res => 'month', render_style => short', }