Pear DB_DataObject
manual does not necessary convey the help needed.

If you have your own experience don't hasitate to share. Especially about solved issues. Once even you could find a solution that saves you precious time.

Any concise note counts.

Let's start:

Someone could save his hair if he realizes that the letter size matter..

story: Automatic Table Linking and Joins
issue: getLink() and getLinks() with the link.ini file does not link
appearance: WHERE part of SQL which selects your linked row is missing, resulting in getting all and chosing the first in table.
fix: doublecheck the letter size of table/column names of tables you are linking.

SQL: SELECT person_id FROM.... SELECT Person_ID... or SELECT peRson_ID... does not matter to MySQL.

But it does in links.ini: