Question

我试图在我的匿名PL / SQL块中捕获异常

DECLARE
    ...

BEGIN
FOR herstell_row IN (
    ...
) 
LOOP
    ...

    DECLARE
        table_does_not_exists exception;
        pragma exception_init( table_does_not_exists, -942 );
    BEGIN
        INSERT INTO SMART_MONITORING_MACHINE_NAV_B (
            MACHINE, 
            NAVIGATION_LEVEL_ID
        ) 
        SELECT 
            old_binding.MACHINE, 
            pv_id 
        FROM 
            SMART_MACHINE_NAV_BINDING old_binding
        WHERE
            old_binding.NAVIGATION_LEVEL_ID = herstell_row.HENAME1;
    EXCEPTION
        WHEN table_does_not_exists THEN null;
    END;

END LOOP;
END;

我知道SMART_MACHINE_NAV_BINDING表在我的情况下不存在，所以我需要嵌套的匿名块来忽略它的代码。但我总是得到这个错误：

错误报告 - ORA-06550：第41行，第14栏： PL / SQL：ORA-00942：表或视图不存在 ORA-06550：第33行，第10栏： PL / SQL：忽略SQL语句

Answer 1

Oracle不知道这个错误table_does_not_exists它是用户定义的，所以你应该在其他人处理时，例如。

Exception
  When Others then
     null;
  -- or at this time you can raise your error table_does_not_exists
    raise table_does_not_exists;
  -- and handle it in another parent block
end;
Exception
   when table_does_not_exists then
     null;
end;

Answer 2

您无法使用不存在的表编译代码，但您可以尝试使用EXECUTE EMMEDIATE执行它：

DECLARE
    ...

BEGIN
FOR herstell_row IN (
    ...
) 
LOOP
    ...

    DECLARE
        table_does_not_exists exception;
        pragma exception_init( table_does_not_exists, -942 );
    BEGIN
      execute immediate 
        'INSERT INTO SMART_MONITORING_MACHINE_NAV_B (
            MACHINE, 
            NAVIGATION_LEVEL_ID
        ) 
        SELECT 
            old_binding.MACHINE, 
            pv_id 
        FROM 
            SMART_MACHINE_NAV_BINDING old_binding
        WHERE
            old_binding.NAVIGATION_LEVEL_ID = :P' using herstell_row.HENAME1;
    EXCEPTION
        WHEN table_does_not_exists THEN null;
    END;

END LOOP;
END;

此处您不需要例外，您可以使用系统视图检查表的存在：

declare
  table_created number;
begin
  select count(*)
    into table_created
    from all_tables
   where table_name = ...
     and owner = ...;

  if table_created > 0 then
     execute immediate 'insert into ...';
  end if;
end;

有关EXECUTE IMMEDIATE声明的更多信息：http://docs.oracle.com/cd/E11882_01/appdev.112/e25519/executeimmediate_statement.htm#LNPLS01317

匿名PL / SQL块检查异常

2 个答案: