Text field

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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


Description

This is a very simple type of metadata field, which is used as a basis for several others.

It stores a string of text. The maximum possible length of the string is 255 bytes.

Note that 255 bytes does not mean 255 characters! UTF-8 can use 1 to 4 bytes to store a character. ASCII characters (a-z,0-9 etc) only use 1 byte so it will store 255 ASCII characters, but less of latin and much less of chinese.

Inheritance

Additional Properties

As for Id fields except for:

name default description
sql_index 0 as for Metadata but with a different default.
text_index 1 as for Metadata but with a different default.

Required Phrases

No additional phrases beyond those required for Id fields.

Database

Text fields are stored in the database as

fieldname VARCHAR(255)

API

See API page.

Examples

Most basic example.

{
    name => 'publisher',
    type => 'text',
},

Allow multiple values.

{
    name => 'corp_creators',
    type => 'text',
    multiple => 1,
},

Create an index in the SQL database table.

{
    name => 'publisher',
    type => 'text',
    sql_index => 1,
},

Do not allow to be indexed for search.

{
    name => 'private',
    type => 'text',
    text_index => 0,
},