如何在 Oracle 中多次更新 table?

How to multi-update the table in Oracle?

我有这些 table 叫做 transaction_line_fact 和 channel_dim:

SQL> desc transaction_line_fact
 Name                                                              Null?    Type
 ----------------------------------------------------------------- -------- --------------------------------------------
 TRANSACTION_ID                                                             NUMBER(20)
 TRANSACTION_LINE_ID                                                        NUMBER(20)
 TRANID                                                                     VARCHAR2(30)
 TRANSACTION_TYPE                                                           VARCHAR2(50)
 TRANDATE                                                                   DATE
 KPI_CHANNEL_SKEY                                                           NUMBER(20)
 KPI_LOCATION_SKEY                                                          NUMBER(20)
 KPI_DEPARTMENT_SKEY                                                        NUMBER(20)
 KPI_ITEM_SKEY                                                              NUMBER(20)
 AMOUNT                                                                     NUMBER(8,2)
 COST                                                                       NUMBER(8,2)
 UNITS                                                                      NUMBER(5)
 KPI_DW_SKEY                                                       NOT NULL NUMBER(20)

SQL> desc channel_dim
 Name                                                              Null?    Type
 ----------------------------------------------------------------- -------- --------------------------------------------
 DATE_CREATED                                                               DATE
 IS_RECORD_INACTIVE                                                         CHAR(1)
 LAST_MODIFIED_DATE                                                         DATE
 LIST_ID                                                                    NUMBER(20)
 LIST_ITEM_NAME                                                             VARCHAR2(20)
 KPI_DW_SKEY                                                       NOT NULL NUMBER(20)
 KPI_DW_INSERT_DATE                                                         DATE
 KPI_DW_UPDATE_DATE                                                         DATE

目前 transaction_line_fact table KPI_CHANNEL_SKEY 中包含空值,但我想借助 channel_dim 中的 KPI_DW_SKEY 列来填充它。

我也试过这样做:

SQL> update transaction_line_fact set kpi_channel_skey = (select c.kpi_dw_skey from channel_dim c join transaction_line_fact t on c.kpi_dw_skey=t.kpi_dw_skey);
update transaction_line_fact set kpi_channel_skey = (select c.kpi_dw_skey from channel_dim c join transaction_line_fact t on c.kpi_dw_skey=t.kpi_dw_skey)
                                                     *
ERROR at line 1:
ORA-01427: single-row subquery returns more than one row


SQL> update transaction_line_fact set kpi_channel_skey = (select kpi_dw_skey from channel_dim) where kpi_channel_skey is null;
update transaction_line_fact set kpi_channel_skey = (select kpi_dw_skey from channel_dim) where kpi_channel_skey is null
                                                     *
ERROR at line 1:
ORA-01427: single-row subquery returns more than one row


SQL> update transaction_line_fact set kpi_channel_skey in (select kpi_dw_skey from channel_dim) where kpi_channel_skey is null;
update transaction_line_fact set kpi_channel_skey in (select kpi_dw_skey from channel_dim) where kpi_channel_skey is null
                                                  *
ERROR at line 1:
ORA-00927: missing equal sign

但它再次显示错误 ORA-01427: single-row subquery returns more than one row

知道如何填充它吗? 非常感谢!

正确的语法是

UPDATE transaction_line_fact f
   SET f.kpi_channel_skey =
          (SELECT c.kpi_dw_skey
             FROM channel_dim c
            WHERE c.kpi_dw_skey = f.kpi_dw_skey);

换句话说,您必须将 channel_dimtransaction_line_fact 连接起来,但不要在子查询中再次指定 table,而是使用 where 子句来加入适当的列。


虽然现在就原理而言这已经“OK”了,但我不知道它是否会(或不会)引发错误; too_many_rows 可能会再次发生,但是 - 在那种情况下 - 如果相同的 kpi_dw_skey channel_dim 包含多个行,你必须决定要做什么 - 你会只取一个(哪个一个?),或者……真的,说不出来。