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如何用变量传递表名实现删除表的操作


  怎样在oracle用变量名传递表名进行查询?这里面我想删除一些过期的没用的费表.
  1.set serveroutput on;
  2.declare
  3.DropTableName   sys.dba_objects%rowtype;
  4.Cursor Object_Name is select OBJECT_NAME FROM  sys.dba_objects where 5.object_type in('TABLE') and
  6.owner='SYSTEM' and created>sysdate-2;
  7.begin
  8.for cnt_var in Object_Name
  9.loop
  10.fetch Object_Name into DropTableName.OBJECT_NAME;
  *11.drop table  DropTableName.OBJECT_NAME;
  12.end loop;
  13.end;
  /
  执行上面的存储过程的时候,出现下面的错误.
  
  DROP TABBLE  DropTableName.OBJECT_NAME;
  *
  ERROR 位于第 9 行:
  ORA-06550: 第 9 行, 第 1 列:
  PLS-00103: 出现符号 "DROP"在需要下列之一时:
  begin case declare end
  exit for goto if loop mod null pragma raise return select
  update while with 
    <<
  close current delete fetch lock insert open rollback
  savepoint set sql execute commit forall merge
   pipe
  符号 "declare在 "DROP" 继续之前已插入。
  ORA-06550: 第 10 行, 第 1 列:
  PLS-00103: 出现符号 "END"在需要下列之一时:
  begin function package
  pragma procedure subtype type use 
   form current cursor
  如将第*11句改为 dbms_output. put_line(DropTableName.OBJECT.NAME)程序执行正确.oracle 不能用变量传递表名?请教!急急,在线等待!!!
  
  drop table  DropTableName.OBJECT_NAME;
  改成
  execute immediate 'drop table ' | |DropTableName.OBJECT_NAME;
  
  直接执行是不行的,用下面的试试:
  
  SQL_STR = 'drop table ' | | DropTableName.OBJECT_NAME ;
  EXECUTE IMMEDATE SQL_STR;
  
  用oracle的内部存储过程包dbms_sql构造sql,然后执行。见下面的例子(摘自sql programing)
  
  PROCEDURE drop_object
  (object_type_in IN VARCHAR2, object_name_in IN VARCHAR2)
  IS
  cursor_id INTEGER;
  BEGIN
  /*
  | | Open a cursor which will handle the dynamic SQL statement.
  | | The function returns the pointer to that cursor.
  */
  cursor_id := DBMS_SQL.OPEN_CURSOR;
  /*
  | | Parse and execute the drop command which is formed through
  | | concatenation of the arguments.
  */
  DBMS_SQL.PARSE
  (cursor_id,
  'DROP '  | | object_type_in  | | ' '  | | object_name_in,
  DBMS_SQL.NATIVE);
  /* Close the cursor. */
  DBMS_SQL.CLOSE_CURSOR (cursor_id);
  EXCEPTION
  /* If any problem arises, also make sure the cursor is closed. */
  WHEN OTHERS
  THEN
  DBMS_SQL.CLOSE_CURSOR (cursor_id);
  END;
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