analyze the memory consumption of one sql

there will be a easy sample of memory consumption caculation

check the block size of your oracle,here are 8192bytes
SQL> show parameter db_block_size;

NAME                                 TYPE        VALUE
———————————— ———– ——————————
db_block_size                        integer     8192

//check the execution plan of sql
SQL> select * from scott.emp;

EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM     DEPTNO
———- ———- ——— ———- ——— ———- ———- ———-
7369 SMITH      CLERK           7902 17-DEC-80        800                    20
7499 ALLEN      SALESMAN        7698 20-FEB-81       1600        300         30
7521 WARD       SALESMAN        7698 22-FEB-81       1250        500         30
7566 JONES      MANAGER         7839 02-APR-81       2975                    20
7654 MARTIN     SALESMAN        7698 28-SEP-81       1250       1400         30
7698 BLAKE      MANAGER         7839 01-MAY-81       2850                    30
7782 CLARK      MANAGER         7839 09-JUN-81       2450                    10
7788 SCOTT      ANALYST         7566 19-APR-87       3000                    20
7839 KING       PRESIDENT            17-NOV-81       5000                    10
7844 TURNER     SALESMAN        7698 08-SEP-81       1500          0         30
7876 ADAMS      CLERK           7788 23-MAY-87       1100                    20

EMPNO ENAME      JOB              MGR HIREDATE         SAL       COMM     DEPTNO
———- ———- ——— ———- ——— ———- ———- ———-
7900 JAMES      CLERK           7698 03-DEC-81        950                    30
7902 FORD       ANALYST         7566 03-DEC-81       3000                    20
7934 MILLER     CLERK           7782 23-JAN-82       1300                    10

14 rows selected.

Elapsed: 00:00:00.03

Execution Plan
———————————————————-
Plan hash value: 3956160932

————————————————————————–
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
————————————————————————–
|   0 | SELECT STATEMENT  |      |    14 |   518 |     3   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| EMP  |    14 |   518 |     3   (0)| 00:00:01 |
————————————————————————–

Statistics
———————————————————-
1  recursive calls
0  db block gets
8  consistent gets
0  physical reads
0  redo size
1415  bytes sent via SQL*Net to client
385  bytes received via SQL*Net from client
2  SQL*Net roundtrips to/from client
0  sorts (memory)
0  sorts (disk)
14  rows processed

//8 consistent gets,you can calculate the exact memory consumption by:
//8 x 8192bytes=65536bytes=64kb