最近公司項目繁忙,實在沒有時間寫博,内心充滿不安。
好在本次遇到一個需要“對比兩個相似schema中table字段結構,并生成Scripts” 的需求,特整理于此,以平民憤 -_-,
背景如下:
1. schemaA是我們的新版本資料庫架構
2. schemaB是我們的舊系統,包含了若幹資料
3. 甲方要求更新必須保留原有交易資料
4. 顯然schemaA、schemaB 從索引結構、序列配置、字段配置 是有多處不同的
我該怎麼處理呢?
我的思路:
1. 直接使用 schemaA 資料庫結構,這樣可以忽略 索引結構、序列配置 的過程
2. 需要将資料從 schemaB insert 至 schemaA 中
3. 但是相對于schemaB ,schemaA已經做了太多字段變更與改進。直接insert 會有一大堆ora- 出來
4. 我需要在insert之前,将schemaB字段調整與schemaA一緻,如果一個個去找,再拼接腳本,我會瘋掉的。。。
5. 那麼我們需要關注 all_tab_cols 這個資料字典
我的腳本:
腳本的設計思路很簡單:
1. 先使用對比的辦法,針對一個table分别生成 add 與 drop SQL,再union。 為過程A
2. 使用遊标周遊兩個schema的table得到table_list , 并循環調用過程A
3. 将得到的SQL儲存至table以便讀取
先檢視一下tablename的情況吧
select * from
(select table_name from user_tables) a
full outer join
(select table_name from all_tables where owner='JS_TEMP') b
on a.table_name=b.table_name
where a.table_name is null or b.table_name is null
sysdba:
grant select any table to jsec;
jsec:
CREATE TABLE T_COMPARE_COLS_SCRIPTS (SCRIPTS VARCHAR2(500))
/
CREATE OR REPLACE PROCEDURE P_COMPARE_COLS_SCRIPTS
(V_TABLE_NAME IN VARCHAR2,
V_SCHEMA_A IN VARCHAR2,
V_SCHEMA_B IN VARCHAR2)
AS
BEGIN
INSERT INTO T_COMPARE_COLS_SCRIPTS
SELECT 'ALTER TABLE '||V_SCHEMA_A||'.'||V_TABLE_NAME||' ADD '||B.COLUMN_NAME||' '||B.DATA_TYPE
||CASE WHEN B.DATA_TYPE IN ('DATE','CLOB','BLOB') THEN ''
ELSE CASE WHEN B.DATA_LENGTH>0 THEN '(' ELSE '' END||B.DATA_LENGTH||CASE WHEN B.DATA_LENGTH>0 THEN ')'
ELSE '' END
END
--||CASE WHEN B.NULLABLE='N' THEN ' NOT NULL' ELSE '' END --我暫時忽略了是否為null的定義,如果需要可以解注
--||CASE WHEN B.DATA_DEFAULT IS NOT NULL THEN '' ELSE '' END
--我這裡暫時還不能處理好預設值的問題,因為資料字典中是LONG類型,不能直接轉換為字元串,但是可以在create table中to_lob ,再to_char
||';'
AS SCRIPTS
FROM
(SELECT COLUMN_NAME,DATA_TYPE,TO_CHAR(DATA_LENGTH) DATA_LENGTH,NULLABLE,DATA_DEFAULT
FROM ALL_TAB_COLS
WHERE OWNER = V_SCHEMA_A
AND TABLE_NAME = V_TABLE_NAME
AND VIRTUAL_COLUMN!='YES') A
FULL OUTER JOIN
(SELECT COLUMN_NAME,DATA_TYPE,TO_CHAR(DATA_LENGTH) DATA_LENGTH,NULLABLE,DATA_DEFAULT
FROM ALL_TAB_COLS
WHERE OWNER = V_SCHEMA_B
AND TABLE_NAME = V_TABLE_NAME
AND VIRTUAL_COLUMN!='YES') B
ON A.COLUMN_NAME = B.COLUMN_NAME
WHERE A.COLUMN_NAME IS NULL
UNION ALL
SELECT 'ALTER TABLE '||V_SCHEMA_A||'.'||V_TABLE_NAME||' DROP COLUMN '||A.COLUMN_NAME||';'
AS SCRIPTS
FROM
(SELECT COLUMN_NAME,DATA_TYPE,TO_CHAR(DATA_LENGTH) DATA_LENGTH
FROM ALL_TAB_COLS
WHERE OWNER = V_SCHEMA_A
AND TABLE_NAME = V_TABLE_NAME
AND VIRTUAL_COLUMN!='YES') A
FULL OUTER JOIN
(SELECT COLUMN_NAME,DATA_TYPE,TO_CHAR(DATA_LENGTH) DATA_LENGTH
FROM ALL_TAB_COLS
WHERE OWNER = V_SCHEMA_B
AND TABLE_NAME = V_TABLE_NAME
AND VIRTUAL_COLUMN!='YES') B
ON A.COLUMN_NAME = B.COLUMN_NAME
WHERE B.COLUMN_NAME IS NULL;
END;
/
CREATE OR REPLACE PROCEDURE P_COMPARE_COL_DRIVER
(V_SCHEMA_DRIVER_A VARCHAR2,
V_SCHEMA_DRIVER_B VARCHAR2)
AS
V_TABLE_DRIVER_NAME VARCHAR2(50);
BEGIN
DELETE FROM T_COMPARE_COLS_SCRIPTS;
DECLARE
CURSOR C_TABLE_LIST IS
SELECT A.TABLE_NAME AS TABLE_NAME_A
FROM (SELECT TABLE_NAME
FROM ALL_TABLES
WHERE OWNER = V_SCHEMA_DRIVER_A) A
INNER JOIN (SELECT TABLE_NAME
FROM ALL_TABLES
WHERE OWNER = V_SCHEMA_DRIVER_B) B
ON A.TABLE_NAME = B.TABLE_NAME
ORDER BY TABLE_NAME_A;
BEGIN
OPEN C_TABLE_LIST;
FETCH C_TABLE_LIST
INTO V_TABLE_DRIVER_NAME;
WHILE C_TABLE_LIST%FOUND LOOP
DBMS_OUTPUT.PUT_LINE(V_TABLE_DRIVER_NAME);
BEGIN
P_COMPARE_COLS_SCRIPTS(V_TABLE_NAME => V_TABLE_DRIVER_NAME,
V_SCHEMA_A => V_SCHEMA_DRIVER_A,
V_SCHEMA_B => V_SCHEMA_DRIVER_B);
END;
FETCH C_TABLE_LIST
INTO V_TABLE_DRIVER_NAME;
END LOOP;
COMMIT;
END;
END;
/
begin
p_compare_cols_scripts (v_table_name => 'BARGAINOR',v_schema_A => 'JSEC',v_schema_B => 'JS_TEMP');
end;
begin
P_COMPARE_COL_DRIVER(v_schema_driver_A => 'JS_TEMP',v_schema_driver_B => 'JSEC');
end;
SELECT * FROM T_COMPARE_COLS_SCRIPTS ORDER BY SCRIPTS
select
'insert into jsec.'||table_name||' select * from js_temp.'||table_name||' nologging;'
from user_tables
where table_name in (select table_name from all_tables where owner='JSEC')
order by table_name