I need to build an expression through which to achieve a rule-based classification by multiple fields. The basic expression could be: "Field 1" = 'Value a' AND "Field 2" = 'Value b' AND "Field 3" = 'Value c' but I need to be able to write in the same rule n expression with the same structure but referring to different values of the same fields, ie
so that each class is composed of the set of elements (features) that satisfy the conditions of the single basic expression. As a second possibility to obtain the same classification I considered the possibility of creating a new column whose values are obtained through a CASE WHEN / THEN expression that contains the same expressions described above, ie:
Can both be correct ways to solve the problem and what can be the correct syntax?