Oracle implements the Generate_series functionality of PostgreSQL

PostgreSQL has a function of generating sequences, which makes it easy to create data. Here I use Oracle to implement the function of the generate_series function of Pgsql.
POSTGRESQL.

t_girl=# SELECT * from Generate_series (1,10);               Generate_series-----------------1 2 3 4 5 6 7 8 9 10 (10 Row Records) Time: 1.290 mst_girl=# select * from generate_s Eries (1,10,2); Generate_series-----------------1 3 5 7 9 (5 line Records) Time: 0.431 mst_girl=# SELECT * from Generate_series (1,10,3);  Generate_series-----------------1 4 7 10 (4 Row Records) Time: 0.879 mst_girl=# SELECT * from Generate_series (2,10,3);  Generate_series-----------------2 5 8 (3 Row Records) Time: 0.867 mst_girl=# Select COUNT (*) From Generate_series (1,1000); Count-------1000 (1 Row Records) Time: 1.142 mst_girl=# Select To_char (Now ()-' 1 days ':: Interval * n, ' yyyy-mm-dd ') as result from Gen   Erate_series (1,10) g (n); Result------------2015-12-08 2015-12-07 2015-12-062015-12-05 2015-12-04 2015-12-03 2015-12-02 2015-12-01 2015-11-30 2015-11-29 (10 Row Records) Time: 17.284 ms 

ORACLE:

12:10:34 sql> SELECT * FROM table (Ytt_generate_series (1,10));                                                                               Column_value------------                                                                               1                                                                               2 3                                                                               4                                                                               5 6                                                                                7 8                                                                              9                                            10                        10 rows have been selected. Used Time: 00:00:00.0212:10:36 sql> select * FROM table (Ytt_generate_series (1,10,2));                                                                               Column_value------------                                                                               1                                                                               3 5                                                                               7  9 used time: 00:00:00.0012:10:54 sql> select * FROM Table (Ytt_generate_series (1,10,3));                                                                               Column_value------------                                                               1                4 7                                                                    10 Used Time: 00:00:00.0012:10:56 sql> select * FROM table (Ytt_generate_series (2,10,3));                                                                               Column_value------------                                                                               2                                                                    5 8 Time used: 00:00:00.0212:11:04 sql> Select COUNT (*) from table (Ytt_generate_series (1,10  00));                                                                            COUNT (*)----------      1000                                                                Time used: 00:00:00.1313:32:13 sql> select To_char (sysdat E-n, ' yyyy-mm-dd ') from table (Ytt_generate_series (1,10)); To_char (  SY----------2015-12-082015-12-072015-12-062015-12-052015-12-042015-12-032015-12-022015-12-012015-11-302015-11-29 has been selected 10 lines. Time used: 00:00:00.01

attached code:

--Declare result set.create or replace type Ytt_num is Object (n number),/create or replace type numbers_table is table O F ytt_num;/--function body.--Created by ytt.--2015/12/9create or replace Function ytt_generate_series (f_start_num numbe r: = 1,--Start number.f_end_num number,  --Finish number.f_step_num Number: = 1--step.) return numbers_table Pipelinedis   list numbers_table: = Numbers_table ();  I number: = 0;  J Number: = 1;begin  I: = F_start_num;  J: = 1;  --Increase nested table ' s size.  List.extend (f_end_num);  --Loop begin.  While I <= F_end_num loop  --initlization.    List (j): = Ytt_num (null);    List (j). N: = i;    Pipe row (List (j));    I: = i + f_step_num;    J: = j + 1;  End Loop;  return;end;/

Oracle implements the Generate_series functionality of PostgreSQL