Use rownum to limit the resultset : rownum « Query Select « Oracle PL/SQL Tutorial

1. Oracle PL/SQL Tutorial
2. Query Select
3. rownum

SQL> describe user_tables;
 Name                               Null?    Type
 ---------------------------------------------------------
 TABLE_NAME                         NOT NULL VARCHAR2(30)
 TABLESPACE_NAME                             VARCHAR2(30)
 CLUSTER_NAME                                VARCHAR2(30)
 IOT_NAME                                    VARCHAR2(30)
 STATUS                                      VARCHAR2(8)
 PCT_FREE                                    NUMBER
 PCT_USED                                    NUMBER
 INI_TRANS                                   NUMBER
 MAX_TRANS                                   NUMBER
 INITIAL_EXTENT                              NUMBER
 NEXT_EXTENT                                 NUMBER
 MIN_EXTENTS                                 NUMBER
 MAX_EXTENTS                                 NUMBER
 PCT_INCREASE                                NUMBER
 FREELISTS                                   NUMBER
 FREELIST_GROUPS                             NUMBER
 LOGGING                                     VARCHAR2(3)
 BACKED_UP                                   VARCHAR2(1)
 NUM_ROWS                                    NUMBER
 BLOCKS                                      NUMBER
 EMPTY_BLOCKS                                NUMBER
 AVG_SPACE                                   NUMBER
 CHAIN_CNT                                   NUMBER
 AVG_ROW_LEN                                 NUMBER
 AVG_SPACE_FREELIST_BLOCKS                   NUMBER
 NUM_FREELIST_BLOCKS                         NUMBER
 DEGREE                                      VARCHAR2(10)
 INSTANCES                                   VARCHAR2(10)
 CACHE                                       VARCHAR2(5)
 TABLE_LOCK                                  VARCHAR2(8)
 SAMPLE_SIZE                                 NUMBER
 LAST_ANALYZED                               DATE
 PARTITIONED                                 VARCHAR2(3)
 IOT_TYPE                                    VARCHAR2(12)
 TEMPORARY                                   VARCHAR2(1)
 SECONDARY                                   VARCHAR2(1)
 NESTED                                      VARCHAR2(3)
 BUFFER_POOL                                 VARCHAR2(7)
 ROW_MOVEMENT                                VARCHAR2(8)
 GLOBAL_STATS                                VARCHAR2(3)
 USER_STATS                                  VARCHAR2(3)
 DURATION                                    VARCHAR2(15)
 SKIP_CORRUPT                                VARCHAR2(8)
 MONITORING                                  VARCHAR2(3)
 CLUSTER_OWNER                               VARCHAR2(30)
 DEPENDENCIES                                VARCHAR2(8)
 COMPRESSION                                 VARCHAR2(8)
 DROPPED                                     VARCHAR2(3)

SQL>
SQL> select table_name, tablespace_name
  2  from user_tables
  3  where rownum < 30
  4  order by table_name;


TABLE_NAME                     TABLESPACE_NAME
------------------------------ ------------------------------
EMPLOYEE_TAB
EMP_DEPT                       SYSTEM
PEOPLE                         SYSTEM
SESS_EVENT
TEMP_ALL_OBJECTS
TRANSACTION_TAB

6 rows selected.

SQL>