代码：

Question

我正在使用Oracle的异构服务（HS）。我有一个名为employee的Microsoft Access表的数据库链接。在使用SQL * Plus的Oracle连接中，我可以描述表的列和数据类型（desc employee）。我也可以从远程表中选择并接收记录。

但是，使用匿名块时，我收到Oracle错误：

ORA-02070: database MSAccessODBC64 does not support TO_NUMBER in this context

MSAccessODBC64是我在Windows 7中配置的ODBC DSN。

代码：

declare
   my_record_position number := 60109;
   my_record employee@MSAccessODBC64bit%rowtype;
begin
   select
      *
   into
      my_record
   from
      eemployee@MSAccessODBC64bit ---->> When I remove the database link, it works
   where
      staff_number = my_record_position ---->> when I remove the where clause, it works
   order by
      staff_number asc;
   dbms_output.put_line(my_record.staff_number);
end;
/

错误：

   declare
      *
   ERROR at line 1:
   ORA-02070: database MSAccessODBC64 does not support TO_NUMBER in this context
   ORA-06512: at line 5

HS是否需要某种问题或选项？我在俯瞰什么？

当我使用替换变量时，它会起作用并显示employee id。

define emp = 60109;
declare
   my_record_position number := 60109;
   my_record employee@MSAccessODBC64bit%rowtype;
begin
   select
      *
   into
      my_record
   from
      employee@MSAccessODBC64bit
   where
      staff_number = &emp
   order by
      staff_number asc;
   dbms_output.put_line('emp=' || my_record.staff_number);
end;
/
emp=60109

PL/SQL procedure successfully completed.

===========initMSAccessODBC64bit.ora for ODBC==============

# This is a sample agent init file that contains the HS parameters that are
# needed for the Database Gateway for ODBC

#
# HS init parameters
#
HS_DESCRIBE_CACHE_HWM   = 4000
HS_FDS_CONNECT_INFO     = MSAccessODBC64bit
HS_FDS_TRACE_LEVEL      = DEBUG
HS_OPEN_CURSORS         = 50
HS_RPC_FETCH_REBLOCKING = ON
HS_RPC_FETCH_SIZE       = 10000
HS_FDS_FETCH_ROWS       = 100
HS_TRANSACTION_MODEL    = READ_ONLY

#This was supposed to fix ORA-02070: database MSAccessODBC64bit does not
#support TO_number in this context
#This didn't work
#EnableWCharSupport      = 0

Answer 1

解决！根据可执行的游标sql语句，HS和ODBC Oracle服务的范围和用法受到限制。解决方法是使用虚拟DBMS_HS_PASSTHROUGH包。这将允许您使用pl / sql变量和绑定变量向远程数据库提交查询。以下示例是上述代码的替代。

实施例

declare
   v_cursor           BINARY_INTEGER;
   my_record_position number := 1234;
   my_record          employees@MSAccessODBC64bit%rowtype;
   my_empid           employees.empid@MSAccessODBC64bit%type;
begin
   v_cursor := DBMS_HS_PASSTHROUGH.open_cursor@MSAccessODBC64bit;
   DBMS_HS_PASSTHROUGH.parse@MSAccessODBC64bit
      (
      v_cursor,
      'select * from employee where empid = ' || my_record_position 
      || 'order by empid asc'
      );
   WHILE DBMS_HS_PASSTHROUGH.fetch_row@MSAccessODBC64bit(v_cursor) > 0
   LOOP
      DBMS_HS_PASSTHROUGH.get_value@MSAccessODBC64bit(v_cursor, 1,my_record.empid);
      dbms_output.put_line('empid=' || my_record.empid);
   end loop;
end;
/

Answer 2

错误表明此比较 -

staff_number = my_record_position

- 正在比较不同的数据类型，这会导致查询DBMS自动尝试将其中一个或两个转换为可能进行比较的数据类型。例如，您无法直接将CHAR与NUMBER进行比较;一个必须CAST到另一个 - TO_NUMBER建议正在发生。

TO_NUMBER是特定于Oracle的函数，Access不支持。您可以通过在查询中添加几个CAST来解决此问题，例如： -

CAST (staff_number AS INT) = CAST (my_record_position AS INT)

如果其中一个已经是INT，则会增加一些不必要的开销，但这对您的使用可能无关紧要。

Oracle PL / SQL，数据库链接和异构服务失败：ORA-02070：数据库MSAccessODBC64bit在此上下文中不支持TO_NUMBER

代码：

错误：

2 个答案:

实施例