CREATE TABLE "Chemical Inventory Location"(
ID D_GENERATOR,
"Inventory ID" D_GENERATED,
"Location ID" D_GENERATED,
Units COMPUTED BY ((SELECT "Chemical Description".Units
FROM "Chemical Description" JOIN
"Chemical Inventory"
ON ("Chemical Description".ID =
"Chemical Inventory"."Description ID")
WHERE "Chemical Inventory".ID =
"Inventory ID")),
...
);

The last line of text causes the error message: Field unknown: "Inventory ID":

WHERE "Chemical Inventory".ID = "Inventory ID"

Given that "Inventory ID" is in the table, how can I make the SELECT statement
in the COMPUTED field recognise its existence?

TIA
--
Raymond Kennington
Programming Solutions
TeamW2W (InfoPower)