what feature to use in oracle standard edition like that of partitioning in oracle enterprise edition

若如初见. 提交于 2019-12-02 02:56:27

Only thing that comes to mind is to have a real table for each 'partition', and then a view than unions them all together. But you'd have to rebuild the view every time you added or removed a 'partition', and there might be performance issues, as well as potential complication with anything except selects - which you could get around with procedures to do insert/update/delete on the relevant underlying table. Probably wouldn't be very easy to create or maintain, or very robust. There's a reason Oracle charge extra for this.

Handmade Partitioning - a working example for Oracle XE/SE

  1. Choose a partitioning key, for example: DOC_DATE - partition for every year.
  2. Create a row type and tables for partitions.

    create type DOCS_ROW_TYPE as object (
        doc_id   NUMBER,
        doc_name VARCHAR2(100),
        doc_date DATE
    );
    
    -- Create partition YOLD table (data from OLD years)
    create table DOCS_YOLD OF DOCS_ROW_TYPE;
    alter table DOCS_YOLD modify doc_id not null;
    alter table DOCS_YOLD modify doc_date not null;
    -- Create primary key
    alter table DOCS_YOLD add constraint DOCS_YOLD_PK primary key (DOC_ID) using index;
    -- Create indexes 
    create index DOCS_YOLD_DATE_IDX on DOCS_YOLD (DOC_DATE);
    create index DOCS_YOLD_NAME_UPCASE_IDX on DOCS_YOLD (UPPER(DOC_NAME));
    
    -- Create partition Y2014 table (data from 2014 years)
    create table DOCS_Y2014 OF DOCS_ROW_TYPE;
    alter table DOCS_Y2014 modify doc_id not null;
    alter table DOCS_Y2014 modify doc_date not null;
    -- Create primary key
    alter table DOCS_Y2014 add constraint DOCS_Y2014_PK primary key (DOC_ID) using index;
    -- Create indexes 
    create index DOCS_Y2014_DATE_IDX on DOCS_Y2014 (DOC_DATE);
    create index DOCS_Y2014_NAME_UPCASE_IDX on DOCS_Y2014 (UPPER(DOC_NAME));
    
    -- Create partition Y2015 table (data from 2015 years)
    create table DOCS_Y2015 OF DOCS_ROW_TYPE;
    alter table DOCS_Y2015 modify doc_id not null;
    alter table DOCS_Y2015 modify doc_date not null;
    -- Create primary key
    alter table DOCS_Y2015 add constraint DOCS_Y2015_PK primary key (DOC_ID) using index;
    -- Create indexes 
    create index DOCS_Y2015_DATE_IDX on DOCS_Y2015 (DOC_DATE);
    create index DOCS_Y2015_NAME_UPCASE_IDX on DOCS_Y2015 (UPPER(DOC_NAME));
    
    -- Create partition Y2016 table (data from 2016 years)
    create table DOCS_Y2016 OF DOCS_ROW_TYPE;
    alter table DOCS_Y2016 modify doc_id not null;
    alter table DOCS_Y2016 modify doc_date not null;
    -- Create primary key
    alter table DOCS_Y2016 add constraint DOCS_Y2016_PK primary key (DOC_ID) using index;
    -- Create indexes 
    create index DOCS_Y2016_DATE_IDX on DOCS_Y2016 (DOC_DATE);
    create index DOCS_Y2016_NAME_UPCASE_IDX on DOCS_Y2016 (UPPER(DOC_NAME));
    
    -- Create partition YNEW table (data from NEW years)
    create table DOCS_YNEW OF DOCS_ROW_TYPE;
    alter table DOCS_YNEW modify doc_id not null;
    alter table DOCS_YNEW modify doc_date not null;
    -- Create primary key
    alter table DOCS_YNEW add constraint DOCS_YNEW_PK primary key (DOC_ID) using index;
    -- Create indexes 
    create index DOCS_YNEW_DATE_IDX on DOCS_YNEW (DOC_DATE);
    create index DOCS_YNEW_NAME_UPCASE_IDX on DOCS_YNEW (UPPER(DOC_NAME));
    
  3. You have to define correct constraints then Oracle will use filters in query execution plan!

    alter table DOCS_YOLD
      add constraint DOCS_YOLD_KEY_CHECK
      check (DOC_DATE < to_date('2014-01-01','yyyy-mm-dd'));
    
    alter table DOCS_Y2014
      add constraint DOCS_Y2014_KEY_CHECK
      check (DOC_DATE >= to_date('2014-01-01','yyyy-mm-dd') and DOC_DATE < to_date('2015-01-01','yyyy-mm-dd'));
    
    alter table DOCS_Y2015
      add constraint DOCS_Y2015_KEY_CHECK
      check (DOC_DATE >= to_date('2015-01-01','yyyy-mm-dd') and DOC_DATE < to_date('2016-01-01','yyyy-mm-dd'));
    
    alter table DOCS_Y2016
      add constraint DOCS_Y2016_KEY_CHECK
      check (DOC_DATE >= to_date('2016-01-01','yyyy-mm-dd') and DOC_DATE < to_date('2017-01-01','yyyy-mm-dd'));
    
    alter table DOCS_YNEW
      add constraint DOCS_YNEW_KEY_CHECK
      check (DOC_DATE >= to_date('2017-01-01','yyyy-mm-dd'));
    
  4. Create a view DOCS_PARTITIONS as all partitions union

    create or replace view docs_partitions as
    select * from docs_yold
    union all
    select * from docs_y2014
    union all
    select * from docs_y2015
    union all
    select * from docs_y2016
    union all
    select * from docs_ynew
    
  5. Create a PK sequence

    create sequence DOCS_MASTER_PK_SEQ
    minvalue 1
    maxvalue 1000000000
    start with 1
    increment by 1
    cache 10;
    
  6. Create a "INSTEAD OF" trigger on the DOCS_PARTITIONS view to redistributing data

    create or replace trigger docs_partitions_insert
      INSTEAD OF insert on docs_partitions  
      for each row
    declare
      v_year number(4);
      v_doc_id docs_partitions.DOC_ID%type;
    begin
      v_doc_id := docs_master_pk_seq.nextval;
      v_year := to_number(to_char(:new.doc_date,'yyyy'));
      if (v_year < 2014) then
        insert into docs_yold (doc_id, doc_name, doc_date)
        values (v_doc_id, :new.doc_name, :new.doc_date);
      elsif (v_year = 2014) then
        insert into docs_y2014 (doc_id, doc_name, doc_date)
        values (v_doc_id, :new.doc_name, :new.doc_date);
      elsif (v_year = 2015) then
        insert into docs_y2015 (doc_id, doc_name, doc_date)
        values (v_doc_id, :new.doc_name, :new.doc_date);
      elsif (v_year = 2016) then
        insert into docs_y2016 (doc_id, doc_name, doc_date)
        values (v_doc_id, :new.doc_name, :new.doc_date);
      else
        insert into docs_ynew (doc_id, doc_name, doc_date)
        values (v_doc_id, :new.doc_name, :new.doc_date);
      end if;  
    end docs_partitions_insert;
    
  7. You can also distributing data via a master table - DOCS_MASTER

    -- Create partition MASTER table (all data)
    create table DOCS_MASTER OF DOCS_ROW_TYPE;
    alter table DOCS_MASTER modify doc_id not null;
    alter table DOCS_MASTER modify doc_date not null;
    -- Create primary key
    alter table DOCS_MASTER add constraint DOCS_MASTER_PK primary key (DOC_ID) using index;
    -- Create indexes 
    create index DOCS_MASTER_DATE_IDX on DOCS_MASTER (DOC_DATE);
    create index DOCS_MASTER_NAME_UPCASE_IDX on DOCS_MASTER (UPPER(DOC_NAME));
    
  8. Create a trigger on the DOCS_MASTER table to redistributing data

    create or replace trigger docs_master_insert
      before insert on docs_master  
      for each row
    declare
      v_year number(4);
    begin
      :new.doc_id := docs_master_pk_seq.nextval;
      v_year := to_number(to_char(:new.doc_date,'yyyy'));
      if (v_year < 2014) then
        insert into docs_yold (doc_id, doc_name, doc_date)
        values (:new.doc_id, :new.doc_name, :new.doc_date);
      elsif (v_year = 2014) then
        insert into docs_y2014 (doc_id, doc_name, doc_date)
        values (:new.doc_id, :new.doc_name, :new.doc_date);
      elsif (v_year = 2015) then
        insert into docs_y2015 (doc_id, doc_name, doc_date)
        values (:new.doc_id, :new.doc_name, :new.doc_date);
      elsif (v_year = 2016) then
        insert into docs_y2016 (doc_id, doc_name, doc_date)
        values (:new.doc_id, :new.doc_name, :new.doc_date);
      else
        insert into docs_ynew (doc_id, doc_name, doc_date)
        values (:new.doc_id, :new.doc_name, :new.doc_date);
      end if;  
    end docs_master_insert;
    
  9. Generate data for test

    declare
      v_i integer;
      v_count integer := 1000000;
    begin
      -- insert docs through the master table
      for v_i in 1..v_count
      loop
            insert into docs_master (doc_name, doc_date)
            values (
                   'DOC-M-'||v_i, 
                   to_date(trunc(DBMS_RANDOM.VALUE(to_char(TO_DATE('2000-01-01','yyyy-mm-dd'),'J'),to_char(TO_DATE('2100-01-01','yyyy-mm-dd'),'J'))),'J')
            );
            if mod(v_i,10000)=0 then
              commit;
              dbms_output.put_line('rows M inserted: '||v_i||', '||(round(100*v_i/v_count))||'%');
            end if;
      end loop;
      commit;
      -- insert docs through the partitions view
      /*
      for v_i in 1..2
      loop
            insert into docs_partitions (doc_name, doc_date)
            values (
                   'DOC-P-'||v_i, 
                   to_date(trunc(DBMS_RANDOM.VALUE(to_char(TO_DATE('2000-01-01','yyyy-mm-dd'),'J'),to_char(TO_DATE('2100-01-01','yyyy-mm-dd'),'J'))),'J')
            );
            if mod(v_i,1000)=0 then
              commit;
              dbms_output.put_line('rows P inserted: '||v_i);
            end if;
      end loop;
      commit;
      */
    end;
    
  10. Select data from the DOCS_PARTITIONS view

    select dp.* 
    from DOCS_PARTITIONS dp 
    where 
      dp.DOC_DATE between to_date('2014-02','yyyy-mm') and to_date('2014-03','yyyy-mm')
    
    -- SQL execution plan with filters!!!
    SELECT STATEMENT, GOAL = ALL_ROWS           0   1   78
     VIEW   PART_TEST   DOCS_PARTITIONS 0   1   78
      UNION-ALL                 
       FILTER                   
        TABLE ACCESS BY INDEX ROWID PART_TEST   DOCS_YOLD   3   11  814
         INDEX RANGE SCAN   PART_TEST   DOCS_YOLD_DATE_IDX  3   833 
       TABLE ACCESS BY INDEX ROWID  PART_TEST   DOCS_Y2014  1   750 55500
        INDEX RANGE SCAN    PART_TEST   DOCS_Y2014_DATE_IDX 1   45  
       FILTER                   
        TABLE ACCESS BY INDEX ROWID PART_TEST   DOCS_Y2015  1   1   74
         INDEX RANGE SCAN   PART_TEST   DOCS_Y2015_DATE_IDX 1   44  
       FILTER                   
        TABLE ACCESS BY INDEX ROWID PART_TEST   DOCS_Y2016  1   1   74
         INDEX RANGE SCAN   PART_TEST   DOCS_Y2016_DATE_IDX 1   47  
       FILTER                   
        TABLE ACCESS BY INDEX ROWID PART_TEST   DOCS_YNEW   14  61  4514
         INDEX RANGE SCAN   PART_TEST   DOCS_YNEW_DATE_IDX  14  5565    
    

Table partitioning is a feature of Oracle Enterprise Edition. To my knowledge, there is no such functionality in Standard Edition.

Would be happy to be proved wrong, mind you...

易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!