动态 sql - 使用循环更新多行

Dynamic sql - update multiple rows with loop

我们有很多 table,其中包含 3 个列(RIDPARTNERSUPPLIER)。我想更新这些列,但只能在 4 table 秒内更新 - 取决于 PK。

所以我开始了一些事情,但我卡住了:

BEGIN
 FOR i IN
  (select table_name from all_tab_columns where column_name = 'RID' /*PK*/ 
   and column_name = 'PARTNER' or column_name = 'SUPPLIER')
 LOOP
  EXECUTE IMMEDIATE 'UPDATE  ' || i.table_name|| 'set PARTNER = :newvalue where PARTNER = :oldavalue and RID = :ridvalue'
  USING (newvalue, oldvalue, ridvalue)
END LOOP 
END

问题:

  1. 我不知道,如何使用此方法更新多个列 (因为在 table 中存在 PartnerSupplier,例如:在一个 table 中是 Partner,在另一个 table 中是 Supplier)
  2. 我只想更新(PartnerSupplier)但只更新1个table,取决于PK
  3. 这是可行的解决方案吗?

您需要在 FOR 循环中使用条件 USING 子句和稍微不同的查询,如下所示:

BEGIN
    FOR I IN (
        SELECT TABLE_NAME
               , PARTNER_COUNT
               , SUPPLIER_COUNT
        FROM (
            SELECT TABLE_NAME
                   , SUM(CASE WHEN COLUMN_NAME = 'RID' THEN 1 ELSE 0 END) AS RID_COUNT
                   , SUM(CASE WHEN COLUMN_NAME = 'PARTNER' THEN 1 ELSE 0 END) AS PARTNER_COUNT
                   , SUM(CASE WHEN COLUMN_NAME = 'SUPPLIER' THEN 1  ELSE 0 END) AS SUPPLIER_COUNT
            FROM ALL_TAB_COLUMNS
            WHERE COLUMN_NAME = 'RID'
                  OR COLUMN_NAME = 'PARTNER'
                  OR COLUMN_NAME = 'SUPPLIER'
        ) WHERE RID_COUNT = 1 AND PARTNER_COUNT + SUPPLIER_COUNT = 1
    ) LOOP
        EXECUTE IMMEDIATE 'UPDATE  '
                          || I.TABLE_NAME
                          || 'set :col_name = :newvalue where :col_name = :oldavalue and RID = :ridvalue'
            USING ( DECODE(PARTNER_COUNT,1,'PARTNER','SUPPLIER'),
                    NEWVALUE, 
                    DECODE(PARTNER_COUNT,1,'PARTNER','SUPPLIER'),
                    OLDVALUE, 
                    RIDVALUE );
    END LOOP;
END;
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