alter session set optimizer_mode=first_rows : Session variable « SQL Plus « Oracle PL / SQL






  1. Oracle PL / SQL
  2. SQL Plus
  3. Session variable

alter session set optimizer_mode=first_rows

    

SQL>
SQL>
SQL>
SQL> create table myTable
  2  as
  3  select rownum id, a.*
  4    from all_objects a
  5   where 1=0
  6  /
SQL>
SQL>
SQL>
SQL> alter session set optimizer_mode=first_rows;
SQL>
SQL> select t1.object_name, t2.object_name
  2    from myTable t1, myTable t2
  3   where t1.object_id = t2.object_id
  4     and t1.owner = 'WMSYS'
  5  /
SQL> alter session set sql_trace=true;
SQL> drop table myTable;








Related examples in the same category

1.alter the session with the ALTER SESSION statement and set the session's time zone forward
2.alter session set nls_date_format = 'dd-MON-yyyy hh24:mi:ss';
3.alter session set OPTIMIZER_MODE = RULE
4.Adjust your session time zone to -08:00, display the contents of your time table.
5.alter session set cursor_sharing = force
6.alter session set use_stored_outlines
7.Event-based call and exception tracing
8.event-based call and exception tracing.
9.SQL trace
10.uses dynamic SQL to issue an ALTER SESSION statement.
11.ALTER SESSION SET QUERY_REWRITE_ENABLED
12.alter session set sql_trace=true
13.sql_trace a stored procedure
14.Set the following session parameters to enable query rewrite:
15.If your session time zone is not US/Central (-06:00), alter your session to Central time:
16.alter session set nls_date_format = 'DD-MON-YYYY HH24:MI:SS'
17.Alter time_zone
18.sessiontimezone, current_timestamp
19.demonstrates the use of DBMS_SQL to execute an ALTER SESSION statement.
20.interaction between ALTER SESSION and autonomous transactions.
21.ALTER SESSION SET SQL_TRACE = TRUE
22.ALTER SESSION SET optimizer_dynamic_sampling
23.alter session set NLS_DATE_FORMAT='DD-MM-YYYY'
24.alter session set current_schema=Smart
25.alter session set db_file_multiblock_read_count
26.alter session set hash_area_size
27.alter session set nls_date_format='dd-mm-yyyy', nls_language=Dutch, nls_currency='Eur'
28.alter session set optimizer_index_cost_adj, alter session set optimizer_index_caching
29.alter session set optimizer_max_permutations=80000
30.alter session set optimizer_mode=all_rows
31.alter session set query_rewrite_integrity=enforced
32.alter session set sort_area_size = 102400000
33.alter session set workarea_size_policy=manual
34.alter system flush shared_pool
35.alter system quiesce restricted
36.alter system resume
37.alter system suspend
38.set optimizer_features_enable = '8.1.5' scope = spfile
39.show filestat
40.show parameter optimizer_features
41.show verify
42.If your session time zone is not US/Central Standard Time (-06:00), alter your session to Central Standard time: