Oracle:grouping and Rollup

Oracle Grouping and rollup simple testing

Sql> SelectDEPARTMENT_ID,sum(Salary) fromEmployeeswheredepartment_idinch(Ten, -, -, -) GROUP by department_id Order  bydepartment_id;department_idSUM(SALARY)------------- -----------           Ten        4400            -       24900            -       58000           -       51608SQL> SelectDepartment_id,first_name,sum(Salary) fromEmployeeswheredepartment_idinch(Ten, -, -, -)Group by(Department_id,first_name) Order  bydepartment_id;department_id first_nameSUM(SALARY)------------- -------------------- -----------           TenJennifer4400            -Alexander3100            -Den11000            -Guy2600            -Karen2500            -Shelli2900            -Sigal2800            -Lex17000            -Neena17000            -Steven24000           -Daniel9000           -Ismael7700           -John8200           -Jose Manuel7800           -Luis6900           -Nancy12008 -rows Selectedsql> SelectDepartment_id,first_name,sum(Salary) fromEmployeeswheredepartment_idinch(Ten, -, -, -)GROUP BY rollup (Department_id,first_name) Order  bydepartment_id;department_id first_nameSUM(SALARY)------------- -------------------- -----------           TenJennifer4400           Ten                             4400            -Alexander3100            -Den11000            -Guy2600            -Karen2500            -Shelli2900            -Sigal2800            -                            24900            -Lex17000            -Neena17000            -Steven24000            -                            58000           -Daniel9000           -Ismael7700           -John8200           -Jose Manuel7800           -Luis6900           -Nancy12008           -                            51608department_id first_nameSUM(SALARY)------------- -------------------- -----------                                        138908 +rows Selectedsql> SelectDEPARTMENT_ID,grouping (department_id), first_name,grouping (first_name),sum(Salary) fromEmployeeswheredepartment_idinch(Ten, -, -, -)GROUP BY rollup (Department_id,first_name) Order  bydepartment_id;department_idGROUPING(department_id) First_NameGROUPING(first_name)SUM(SALARY)------------- ----------------------- -------------------- -------------------- -----------           Ten                       0Jennifer0        4400           Ten                       0                                         1        4400            -                       0Alexander0        3100            -                       0Den0       11000            -                       0Guy0        2600            -                       0Karen0        2500            -                       0Shelli0        2900            -                       0Sigal0        2800            -                       0                                         1       24900            -                       0Lex0       17000            -                       0Neena0       17000            -                       0Steven0       24000            -                       0                                         1       58000           -                       0Daniel0        9000           -                       0Ismael0        7700           -                       0John0        8200           -                       0Jose Manuel0        7800           -                       0Luis0        6900           -                       0Nancy0       12008           -                       0                                         1       51608department_idGROUPING(department_id) First_NameGROUPING(first_name)SUM(SALARY)------------- ----------------------- -------------------- -------------------- -----------                                    1                                         1      138908 +Rows selected

Rollup for subtotal and by group statistics.
Grouping (department_id) and Grouping (first_name)
If the current column is in an empty behavior, it is displayed as 1, not empty, and is displayed as 0;

Oracle:grouping and Rollup