-666 Variable variable-name must be declared INTEGER or SMALLINT.

In a FOR statement, loop variables that contain ranges must be declared to be INT or SMALLINT.

Example of error:

DEFINE var CHAR(10); FOR var IN (e1, e2 TO e3, e4) -- error ... END FOR;

Correction: Because the FOR statement contains a range operator (the TO clause), var must be declared as INT or SMALLINT.