The spacing of the gobo and the lens may be varied to alter the size and focus of the image. A gobo in a gobo holder, which goes in a stage lighting instrument. The discolored portion is oxidation of the stainless steel caused by the high temperature of the lamp, but the gobo is still usable.he spacing of the gobo and the lens may be varied to alter the size and focus of the image. A gobo in a gobo holder, which goes in a stage lighting instrument. The discolored portion is oxidation of the stainless steel caused by the high temperature of the lamp, but the gobo is still usable.
The column â%.*lsâ cannot be modified because it is either a computed column or is the result of a UNION operator. The column â%.*lsâ cannot be modified because it is either a computed column or is the result of a UNION operator.
To create a virtual or computed by column use either the create table or alter table â¦. add column clause. This special column computes a value when selected or when. referenced in a WHERE clause. Consider this simple example: SQL> create table PERSON (. cont> (employee_id integer, cont> employee_id_disp computed by.