These code examples are from the "Preparing for 4D v14 Journaling" Webinar.

To set an existing field to be a Primary Key:

Begin SQL    ALTER TABLE Table_1 ADD PRIMARY KEY( myUUID); End SQL

To create a brand new Primary Key:

Begin SQL     ALTER TABLE Table_1 ADD TRAILING myUUID UUID AUTO_GENERATE PRIMARY KEY; End SQL

An example of adding a new Primary Key named "myUUID" to every table in the database:

C_TEXT($sql_t;$tableName_t) C_LONGINT($curTable_l;$numTables_l) $numTables_l:=Get last table number For ($curTable_l;1;$numTables_l)    $sql_t:=""    If (Is table number valid($curTable_l))       $tableName_t:=Table name($curTable_l)       $sql_t:=$sql_t+"ALTER TABLE ["+$tableName_t+"] "       $sql_t:=$sql_t+"ADD TRAILING myUUID UUID AUTO_GENERATE PRIMARY KEY;"       Begin SQL          EXECUTE IMMEDIATE :$sql_t;       End SQL    End if End for