Oracle-Multiple count statistics a table with multiple fields equal to a value

Excerpt: https://www.linuxidc.com/Linux/2012-06/62894.htm

When the case condition then condition is true the value of the else condition is false when the value end

--Single query unify the number of times a field equals a value

Select COUNT (M.underwriteflag) from prpcmain m where m.underwriteflag= ' 1 '  ;--720407select count (M.nationflag) from Prpcmain m where m.nationflag= ' 1 '         --720422
Count ( case and then

　　

Oracle-Multiple count statistics a table with multiple fields equal to a value