Database.com Metadata API Developer's Guide - Salesforce.com

Metadata TypesCustomFieldField NametrueValueIndexedtypeuniquevisibleLineswriteRequiresMasterReadField TypebooleanFieldTypebooleanintbooleanDescriptionFor more information, see “Report on Historical Trends”in the Database.com Help.This is only relevant for a checkbox field. If set, true valuesare built into the index. This field has been deprecated asof API version 14.0 and is only provided for backwardcompatibility.Required. Indicates the field type for the field. Valid valuesare enumerated in FieldType.Indicates whether the field is unique (true) or not(false).Indicates the number of lines displayed for the field.Sets the minimum sharing access level required on themaster record to create, edit, or delete child records. Thisfield applies only to master-detail or junction object customfield types.• true—Allows users with “Read” access to the masterrecord permission to create, edit, or delete child records.This setting makes sharing less restrictive.• false—Allows users with “Read/Write” access to themaster record permission to create, edit, or delete childrecords. This setting is more restrictive than true, andis the default value.For junction objects, the most restrictive access from thetwo parents is enforced. For example, if you set to trueon both master-detail fields, but users have “Read” accessto one master record and “Read/Write” access to the othermaster record, users won't be able to create, edit, or deletechild records.Custom fields use additional data types. For more information, see Metadata Field Types on page 107.EncryptedFieldMaskCharThis field type is used in maskChar. It is a string with two valid values: asterisk or X. For more information on encryptedfields, see About Encrypted Custom Fields in the Database.com online help.EncryptedFieldMaskTypeThis field type is used in maskType. Valid values are:allAll characters in the field are hidden. This option is equivalent to the Mask All Characters option in Database.com.creditCardThe first 12 characters are hidden and the last four display. This option is equivalent to the Credit Card Numberoption in Database.com.91