In your syntax FIELD is not evaluated, but SQL look for a field with name FIELD in the database table...
Sample to try
" Some work area DATA: cnt TYPE i, fieldname TYPE fieldname VALUE 'ERVOL', tabname TYPE tabname VALUE 'MARA', text TYPE string, dmax TYPE REF TO data, dsum TYPE REF TO data. FIELD-SYMBOLS: <max> TYPE ANY, <sum> TYPE ANY. * Create fields adequate to reveive aggegated values in SQL statement CONCATENATE tabname '-' fieldname INTO text. CREATE DATA dmax TYPE (text). ASSIGN dmax->* TO <max>. CREATE DATA dsum TYPE (text). ASSIGN dsum->* TO <sum>. * Execute SQL request (will only pass once in loop, required as Abap doesn't know we use aggregates) CONCATENATE 'COUNT( ' fieldname ' ) MAX( ' fieldname ' ) SUM( ' fieldname ')' INTO text RESPECTING BLANKS. SELECT (text) INTO (cnt,<max>,<sum>) FROM (tabname). ENDSELECT.
Regards,
Raymond