基于历史表创建视图

5
我想基于包含历史表的数据库创建SQL视图。
在无法更新数据库表的情况下,您的最佳解决方案(快速而有效)是什么。我只能创建视图。
这是背景信息:
我的应用程序管理合同。合同具有一般信息,并与联系人,法律引用和组合相关联。当更新完成时,在历史记录表中添加新行(新ID_HIST)。如果对联系人,法律引用或组合进行更新,则在contract_HIST表中也会添加新行(具有相同的ID_HIST)。
我的目的是创建一个视图,以显示对行(ID HIST)进行的更新与先前ID HIST相比如何:

enter image description here

因此,对于每个新的更新(对于特定日期的要求,由ID HIST给出),我们可以看到一般信息、联系人、法律参考或/和组合是否已更新。
以下是数据库的结构:

enter image description here

enter image description here

在此表格中,一个或多个投资组合可以被指定给同一更新的合同。
信息提示:例如,在新的更新过程中,如果已删除合同的联系人,则为该合同添加了一行新的ID_HIST的contract_hist,但不会在contact_hist表中添加新行。法律参考和投资组合也是如此。
这里的视图应该显示:

enter image description here

这里是用于测试的数据库脚本:

    --------------------------------------------------------  
-- DDL for Table CONTACT_HIST  
--------------------------------------------------------  

  CREATE TABLE "CONTACT_HIST"   
   (     "ID_HIST" NUMBER,   
     "ID_CONTRAT" NUMBER,   
     "NAME_CONTACT" VARCHAR2(20 BYTE)  
   ) SEGMENT CREATION IMMEDIATE   
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255   
 NOCOMPRESS LOGGING  
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645  
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1  
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)  
  TABLESPACE "RAM" ;  
REM INSERTING into BO.CONTACT_HIST  
SET DEFINE OFF;  
Insert into BO.CONTACT_HIST (ID_HIST,ID_CONTRAT,NAME_CONTACT) values (1,1,'Bernard');  
Insert into BO.CONTACT_HIST (ID_HIST,ID_CONTRAT,NAME_CONTACT) values (1,1,'Jean');  
Insert into BO.CONTACT_HIST (ID_HIST,ID_CONTRAT,NAME_CONTACT) values (2,1,'Nicolas');  
Insert into BO.CONTACT_HIST (ID_HIST,ID_CONTRAT,NAME_CONTACT) values (2,1,'Jean');  
Insert into BO.CONTACT_HIST (ID_HIST,ID_CONTRAT,NAME_CONTACT) values (3,2,'Nicolas');  
Insert into BO.CONTACT_HIST (ID_HIST,ID_CONTRAT,NAME_CONTACT) values (5,2,'Nicolas');  

--------------------------------------------------------  
-- DDL for Table CONTRAT_HIST  
--------------------------------------------------------  

  CREATE TABLE "BO"."CONTRAT_HIST"   
   (     "ID_HIST" NUMBER,   
     "DATE_CREATION" DATE,   
     "ID_CONTRAT" NUMBER,   
     "TITRE_CONTRAT" VARCHAR2(250 BYTE),   
     "DESCRIPTION" VARCHAR2(250 BYTE),   
     "BUDGET" NUMBER  
   ) SEGMENT CREATION IMMEDIATE   
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255   
 NOCOMPRESS LOGGING  
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645  
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1  
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)  
  TABLESPACE "RAM" ;  
REM INSERTING into BO.CONTRAT_HIST  
SET DEFINE OFF;  
Insert into BO.CONTRAT_HIST (ID_HIST,DATE_CREATION,ID_CONTRAT,TITRE_CONTRAT,DESCRIPTION,BUDGET) values (1,to_date('01-JAN-15','DD-MON-RR'),1,'Contrat 1 ','Contrat Informatique ',20000);  
Insert into BO.CONTRAT_HIST (ID_HIST,DATE_CREATION,ID_CONTRAT,TITRE_CONTRAT,DESCRIPTION,BUDGET) values (2,to_date('15-JAN-15','DD-MON-RR'),1,'Contrat 1 ','Contrat Informatique ',50000);  
Insert into BO.CONTRAT_HIST (ID_HIST,DATE_CREATION,ID_CONTRAT,TITRE_CONTRAT,DESCRIPTION,BUDGET) values (3,to_date('02-FEB-15','DD-MON-RR'),2,'Contrat 2 ','Contrat Santé ',10000);  
Insert into BO.CONTRAT_HIST (ID_HIST,DATE_CREATION,ID_CONTRAT,TITRE_CONTRAT,DESCRIPTION,BUDGET) values (4,to_date('01-MAR-15','DD-MON-RR'),2,'Contrat 2 ','Contrat Consommateur ',30000);  
Insert into BO.CONTRAT_HIST (ID_HIST,DATE_CREATION,ID_CONTRAT,TITRE_CONTRAT,DESCRIPTION,BUDGET) values (5,to_date('01-JUL-15','DD-MON-RR'),1,'Contrat 1 ','Contrat Informatique ',50000);  
--------------------------------------------------------  
-- DDL for Index CONTRAT_HIST_PK  
--------------------------------------------------------  

  CREATE UNIQUE INDEX "BO"."CONTRAT_HIST_PK" ON "BO"."CONTRAT_HIST" ("ID_HIST")   
  PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS   
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645  
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1  
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)  
  TABLESPACE "RAM" ;  
--------------------------------------------------------  
-- Constraints for Table CONTRAT_HIST  
--------------------------------------------------------  

  ALTER TABLE "BO"."CONTRAT_HIST" ADD CONSTRAINT "CONTRAT_HIST_PK" PRIMARY KEY ("ID_HIST")  
  USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 COMPUTE STATISTICS   
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645  
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1  
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)  
  TABLESPACE "RAM"  ENABLE;  
  ALTER TABLE "BO"."CONTRAT_HIST" MODIFY ("ID_HIST" NOT NULL ENABLE);  

--------------------------------------------------------  
-- DDL for Table LEGAL_REFERENCE_HIST  
--------------------------------------------------------  

  CREATE TABLE "BO"."LEGAL_REFERENCE_HIST"   
   (     "ID_HIST" NUMBER,   
     "ID_CONTRAT" NUMBER,   
     "LEG_REF_NAME" VARCHAR2(250 BYTE)  
   ) SEGMENT CREATION IMMEDIATE   
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255   
 NOCOMPRESS LOGGING  
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645  
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1  
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)  
  TABLESPACE "RAM" ;  
REM INSERTING into BO.LEGAL_REFERENCE_HIST  
SET DEFINE OFF;  
Insert into BO.LEGAL_REFERENCE_HIST (ID_HIST,ID_CONTRAT,LEG_REF_NAME) values (1,1,'45 - Technologies et Systeme d''Information');  
Insert into BO.LEGAL_REFERENCE_HIST (ID_HIST,ID_CONTRAT,LEG_REF_NAME) values (2,2,'105 - Consommateur et Santé');  
Insert into BO.LEGAL_REFERENCE_HIST (ID_HIST,ID_CONTRAT,LEG_REF_NAME) values (5,1,'27 - Services');  

--------------------------------------------------------  
-- DDL for Table PORTFOLIO_HIST  
--------------------------------------------------------  

  CREATE TABLE "BO"."PORTFOLIO_HIST"   
   (     "ID_HIST" NUMBER,   
     "ID_CONTRAT" NUMBER,   
     "PORTFOLIO_ID" NUMBER,   
     "PORTFOLIO_NAME" VARCHAR2(250 BYTE),   
     "PORTFOLIO_VALUE" NUMBER  
   ) SEGMENT CREATION IMMEDIATE   
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255   
 NOCOMPRESS LOGGING  
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645  
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1  
  BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)  
  TABLESPACE "RAM" ;  
REM INSERTING into BO.PORTFOLIO_HIST  
SET DEFINE OFF;  
Insert into BO.PORTFOLIO_HIST (ID_HIST,ID_CONTRAT,PORTFOLIO_ID,PORTFOLIO_NAME,PORTFOLIO_VALUE) values (2,1,1,'Portfolio 1',5000);  
Insert into BO.PORTFOLIO_HIST (ID_HIST,ID_CONTRAT,PORTFOLIO_ID,PORTFOLIO_NAME,PORTFOLIO_VALUE) values (2,1,2,'Portfolio 2',7000);  
Insert into BO.PORTFOLIO_HIST (ID_HIST,ID_CONTRAT,PORTFOLIO_ID,PORTFOLIO_NAME,PORTFOLIO_VALUE) values (4,2,1,'Portfolio 1',2000);  
Insert into BO.PORTFOLIO_HIST (ID_HIST,ID_CONTRAT,PORTFOLIO_ID,PORTFOLIO_NAME,PORTFOLIO_VALUE) values (4,2,2,'Portfolio 2',8000);  
commit;  

2
你能把这个做成一个fiddle吗? - Thomas Tschernich
你好,coeurdange57,我的解决方案怎么样了?有帮到你吗? - PT_STAR
1个回答

1

首先:创建一个存储函数(或在包中创建一个函数),如下所示:

create or replace function test_history(i_contract_id  in number,
                                        i_date_created in date,
                                        i_type         in varchar2)
  return varchar2 is
  l_sql    varchar2(1000);
  l_result number;
begin
  l_sql := 'select 1 from test_history_tb where id_contract = :1 and date_creation = :2 and ' ||
           i_type || ' = :3 and rownum = 1';
  execute immediate l_sql
    into l_result
    using i_contract_id, i_date_created, 'update';

  return('update');

exception
  when no_data_found then
    return('no_update');
end;

第二步:根据函数创建查询。
create view xxx as

select id_contract, date_creation,
       test_history(a.id_contract, a.date_creation, 'general_info') general_info,
       test_history(a.id_contract, a.date_creation, 'contract') contract,
       test_history(a.id_contract, a.date_creation, 'legal') legal,
       test_history(a.id_contract, a.date_creation, 'portfolio') portfolio
from test_history_tb a
group by a.id_contract, a.date_creation;

这个解决方案不是很快,因为对于每一行,我们都需要调用一个函数。但是如果你使用where子句过滤数据,它会是一种替代方法。
表格中的示例数据: enter image description here ... 这是视图查询的样子: enter image description here

使用 Twisted 的技巧,在 SELECT 语句中调用一个包含动态 SQL 的函数。甚至不知道这是允许的。 - Thomas Tschernich
我很少使用它,只有在数据量较小的表格(或where子句)上使用,因为那会影响性能。 - PT_STAR

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