| This article outlines the database structure for the MMv4 product_field database table. 
 
 idPrimary Key of the table.
 int(10) | unsigned | auto increment | primary key | indexed
display_orderDetermines the order in which the field is listed on-screen in the Product Editor and other places.
 int(10) | unsigned | indexed
 
titleDescriptive title of the field. This will be displayed with the field in any form in which the field is included.
 varchar(255)
descriptionDescription of the field. This will be displayed with the field in any form in which the field is included. It is a good place to include instructions.
 varchar(255)
input_typeThe type of field, typically: text, dropdown, list_single, list_multi, radio. ("text_single" and "text_multi" will no longer need to be specified by the user. These are replaced by the "text" option. If a text field is set to have more than 1 line, the system will automatically change it to a "text_multi" field when it is displayed on a web page.)
 varchar(255)
 
notesInformation about the field. Only viewable within the administration area.
 text
 
activeThe field's active status. Inactive fields are not displayed on any page that they otherwise would be.
 int(10) | unsigned | Values: 0/timestamp | Default: 1 | indexed
is_uniqueWhether or not the value of the field must be unique. If greater than zero, then no other entry for this same field will be allowed to have the same value.
 int(10) | unsigned | Values: 0/timestamp | Default: 0
num_linesThe number of lines that a multi-line text field will contain. Only applicable if the type is a text field. If set to "1", then the text field will automatically display it as a single-line"text" input field instead of a multi-line "textarea" input field.
 int(10) | unsigned
requiredWhether or not the field may be left blank or be submitted with an empty value.
 int(10) | unsigned | Values: 0/timestamp | Default: 0
strictIf the field's value is greater than zero, then only letters, numbers and underscores will be allowed in the value of the submitted field.
 int(10) | unsigned | Values: 0/timestamp | Default: 0
encryptIf set to a value greater than zero, then the value of the submitted field will be encrypted prior to being saved in the database. Note that encrypted fields cannot be searched by the search tools in the administration or storefront areas.
 int(10) | unsigned | Values: 0/timestamp | Default: 0
internal_onlyIf set to a value greater than zero, then the value of the submitted field will not be displayed outside of the store's Administration area.
 int(10) | unsigned | Values: 0/timestamp | Default: 0 | indexed
include_in_emailIf set to a value greater than zero, then the value of the submitted field will be included in any email correspondence generated by the software that includes information about the customer account.
 int(10) | unsigned | Values: 0/timestamp | Default: 0 | indexed
 
maxlengthDetermines the maximum number of characters that may be entered into single-line text fields.
 int(10) | unsigned
 
default_valueThe default value for this field.
 varchar(255) | indexed
 
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