Records in a LifeLines database may refer to other records via cross-reference links. The lineage-linked references are maintained directly by LifeLines through operations found in the browsing mode menus. These references are the links from a person to families (1 FAMC and 1 FAMS), and the links from a family to persons (1 HUSB, 1 WIFE and 1 CHIL). Because LifeLines maintains these links you are not allowed to change these lines when you are editing records. There are a couple of seeming exceptions to this rule. For example, you may change the order of 1 CHIL lines in a family record in order to change the order of children in a family, and you may change the order of 1 FAMS lines in a person record to change the order of families the person was a spouse or parent in. These operations are allowed because they don't affect which person records refer to which family records and vice versa.
Besides the lineage-links that are maintained by LifeLines, you may place your own links in records. Probably the most common example of this is referring events within a person record to the record of the information source for the event. For example:
Example 1-14. Example of referring events from a person record
0 @I23@ INDI
1 NAME Thomas/Whitmore/
1 BIRT
2 DATE about 1615
2 PLAC England
2 SOUR @S3@
...
0 @S3@ SOUR
1 REFN cat
1 TITL New England Marriages Prior to 1700
1 AUTH Clarence Almon Torrey
...The 2 SOUR @S3@ line in the person record refers to the source record. LifeLines allows any specific structure within a record (in this case a birth event) to refer to another record. It is not possible to refer to a specific location within another record, though this may be supported eventually.
This example implies that when linking one record to another you must know the key of the target record (S3 in the example). This is not desirable because internal record keys may change when the records are exported from one database or imported to another.
Because internal key values are not permanent, LifeLines allows you to assign a permanent user-defined key to any record in the database using the 1 REFN line. The value of this line is a string that you choose as your permanent key value for the record. When adding a link to a record that has a user REFN key value, you may use that value instead of the internal key value. For example, when adding the person in the previous example you could edit the new record as follows:
Example 1-15. Example of adding a new person
0 INDI
1 NAME Thomas/Whitmore/
1 BIRT
2 DATE about 1615
2 PLAC England
2 SOUR <cat>Instead of using the actual key value of the source, S3, the REFN value cat was used. The REFN value must be enclosed by angle brackets when used this way. LifeLines automatically replaces the REFN link with the proper internal key value when the record is stored in the database.
The REFN value may also be used when searching for person, source, event and user-defined records. You should not add more than one REFN line to a record, and every REFN value should be unique.