Updating field data using left join

[#1]

Have a scenario where a field has to be created based on a general part basis and then that field needs to be updated based on a more specific basis. Thought that the process could be done using left joins as follows but that is not the case. Have a workaround, but wondering if there is another way along these lines. Thanks.

//add the class by part (General)

LEFT JOIN (KeyLink)

LOAD

GGPN AS Part,

GCLASS AS Class

RESIDENT ClassGeneral;

// add the class by parent number & part number (Specific)

LEFT JOIN (KeyLink)

LOAD

ClassKey AS Key2,

SCLASS AS Class

RESIDENT ClassSpecific;

[#2]

hi,

can you add the structure of Keylink table.

Thanks & Best Regards,

Kuldeep Tak

[#3]

The initial structure consists of just the fields Key2 and Part. The script attempts to first add the Class field based on a Part field link and then update the class field based on a Key2 link.