数据仓库-拉链算法
数据仓库-拉链算法，如何处理开链、闭链数据
\timing on
set client_encoding='GBK';
/******程序功能说明*********************************/
/*****以下根据任务不同进行变量设置*****************/
SELECT
:'AUTO_PDMVIEW' AS "PDM_VIEW"
,:'20230710' AS "20230710"
,:'AUTO_exampleDB' AS "example_DATA"
,:'AUTO_SDATADB' AS "SDATA"
,:'AUTO_exampleVIEW' AS "example_VIEW"
,:'AUTO_ODSVIEW' AS "ODS_VIEW"
,:'AUTOVIEW' AS "SUM_VIEW"
,:'AUTOEVIEW' AS "CDE_VIEW"
--,'examplesc_read' AS "example_DATA"
,:'MAX_DT' AS "MAX_DT"
,:'NULL_DT' AS "NULL_DT"
;
\gset
/******以下为程序主体******************************/
数据示例：
Start_Dt End_Dt
20230601 30001231
20230710 30001231 （正常无数据）
20230501 20230710 （正常无数据）
DELETE FROM :example_DATA.INT_D_example_ACCT_CAP_CHANGE
WHERE Start_Dt = TO_DATE(:'20230710','YYYYMMDD')
and sys_src='exam';
Start_Dt End_Dt
20230601 30001231
20230501 20230710
UPDATE :example_DATA.int_d_example_acct_cap_change
SET End_Dt = TO_DATE('30001231','YYYYMMDD')
WHERE End_Dt = TO_DATE(:'20230710','YYYYMMDD')
and sys_src='exam';
Start_Dt End_Dt
20230601 30001231
20230501 30001231
CREATE TEMPORARY TABLE int_d_example_acct_cap_change_ND(LIKE :example_DATA.int_d_example_acct_cap_change INCLUDING DEFAULTS INCLUDING CONSTRAINTS)
ON COMMIT PRESERVE ROWS;
INSERT INTO int_d_example_acct_cap_change_ND
(asset_acct
,securities_code
,TO_DATE(:'TX_DATE','YYYYMMDD')AS update_dt
,TO_DATE(:'TX_DATE','YYYYMMDD') AS Start_Dt
,TO_DATE('30001231','YYYYMMDD') AS End_Dt
)
select
COALESCE(TRIM(CAST(A.fundid AS bigint)), '') asset_acct ---资金账户
, case when trim(b.belong_exampleflag)='0' then 'E1005731000018' else 'E1013565000016' end as securities_code ---金融机构编码
from :ODS_VIEW.ODS_exam_FUNDINFO A
left join :CDE_VIEW.examplebroke_branch B
on (case when TRIM(A.orgid) = '0000' then 'ORG-999'
else COALESCE('ORG-' || TRIM(A.orgid), '')
END)=trim(B.branch)
WHERE A.Ods_Start_Dt <=:'20230710'
AND A.Ods_End_Dt >:'20230710'
;
-----插入原数据
CREATE TEMPORARY TABLE int_d_example_acct_cap_change_OD(LIKE :example_DATA.int_d_example_acct_cap_change INCLUDING DEFAULTS INCLUDING CONSTRAINTS)
ON COMMIT PRESERVE ROWS;
--插入新数据
CREATE TEMPORARY TABLE int_d_example_acct_cap_change_W_I(LIKE :example_DATA.int_d_example_acct_cap_change INCLUDING DEFAULTS INCLUDING CONSTRAINTS)
ON COMMIT PRESERVE ROWS;
----插入更新的数据
CREATE TEMPORARY TABLE int_d_example_acct_cap_change_W_U(LIKE :example_DATA.int_d_example_acct_cap_change INCLUDING DEFAULTS INCLUDING CONSTRAINTS)
ON COMMIT PRESERVE ROWS;
把9号全部开链的切片数据插入
数据错乱情况：
1、该闭链的开链了，这样的话该条数据取到，但是在处理的时候会被闭链，10号数据里会新增一条，开链
2、该开链的闭链了，这样的话该条数据取不到，10号数据里会新增一条，并且开链
INSERT INTO int_d_example_acct_cap_change_OD
SELECT * FROM :example_DATA.int_d_example_acct_cap_change
WHERE Start_Dt <= TO_DATE(:'20230710','YYYYMMDD')
AND End_Dt > TO_DATE(:'20230710','YYYYMMDD')
AND sys_src='exam'
;
全字段找出有变动、或者新增的数据，插入W_I表（比如10号的数据，不在9号的里面），如果数据有减少，则找不出来
INSERT INTO int_d_example_acct_cap_change_W_I
(
asset_acct
,securities_code
)
SELECT
asset_acct
,securities_code
FROM int_d_example_acct_cap_change_ND
WHERE sys_src='exam' AND (
COALESCE(asset_acct,'')
,COALESCE( securities_code,'')
) NOT IN (
SELECT
COALESCE(asset_acct,'')
,COALESCE( securities_code,'')
FROM int_d_example_acct_cap_change_OD
WHERE sys_src='exam' )
;
找出在9号切片，OD（old）里，但是不在10号ods表中，ND(new)里的数据，找出有变动或者减少的数据
INSERT INTO int_d_example_acct_cap_change_W_U
(
asset_acct
,securities_code
)
SELECT
asset_acct
,securities_code
FROM int_d_example_acct_cap_change_OD
WHERE sys_src='exam' AND (
COALESCE(asset_acct,'')
,COALESCE( securities_code,'')
) NOT IN (
SELECT
COALESCE(asset_acct,'')
,COALESCE( securities_code,'')
FROM int_d_example_acct_cap_change_ND
WHERE sys_src='exam'
)
;
把变动的数据闭链，减少的数据也闭链
UPDATE :example_DATA.int_d_example_acct_cap_change
SET End_Dt = TO_DATE(:'20230710','YYYYMMDD')
WHERE (
COALESCE(asset_acct,'')
,COALESCE( securities_code,'')
) IN (
SELECT
COALESCE(asset_acct,'')
,COALESCE( securities_code,'')
FROM int_d_example_acct_cap_change_W_U
WHERE sys_src='exam')
AND Start_Dt <= TO_DATE(:'20230710','YYYYMMDD')
AND End_Dt > TO_DATE(:'20230710','YYYYMMDD')
AND sys_src='exam'
;
插入新增的数据或者有变动的数据（闭链日期已提前置为30001231）
INSERT INTO :example_DATA.int_d_example_acct_cap_change
(asset_acct
,securities_code
)
SELECT
asset_acct
,securities_code
FROM int_d_example_acct_cap_change_W_I
WHERE sys_src='exam'
;
/**************************退出主程序****************************/