Contains one entry for each attachment. The actual attachments contents are stored in a dedicated table: attachment_contents.
Structure of attachments
attachment_id
integer
PRIMARY KEY
Unique internal identifier for the attachment.
mail_idinteger
The internal unique ID of the mail message to which the attachment belongs.
REFERENCES mail
content_typecharacter varying(300)
The mime type of the attachment such as 'image/jpeg', 'text/plain', 'message/rfc822'...
content_sizeinteger
The attachment's size in bytes.
filenamecharacter varying(300)
The attachment's filename, if present.
charsetcharacter varying(30)
The character set for text contents (when content_type starts with 'text/'). Typical values are 'utf-8', 'iso-8859-1', 'us-ascii', ...
mime_content_idtext
A string identifying the MIME part's content_id for the attachment. Other attachments may refer to this ID. For example HTML parts use <img src="cid:content_id_of_part"> to embed an attached picture. The use and syntax of content-ID is described in RFC 2392.
Tables referencing attachments via Foreign Key Constraints