带动态pl / sql的where子句中的字符串变量

Question

我有以下代码：

declare
  instr varchar2(20);
  num_no number;

begin 
    select AR_ID, ID
    into instr, num_no
    from quelle_match
    where ID = 1;

      execute immediate 'CREATE or replace VIEW interm2 AS
      SELECT AR_ID, kurs,
        ((TO_CHAR(to_date(di.kursdatum,''dd.mm.yyyy''),''YYYYMMDD''))+    (TO_CHAR(to_date(di.verfall,''dd.mm.yyyy''),''YYYYMMDD''))) AS dumdate
      FROM daten_import di 
      where di.AR_ID = '||instr||'';      

  -- where di.AR_ID = ''GXIndex''';

end ;

我收到错误b / c instr无效。 当我用实际的字符串GXIndex替换变量时，代码起作用。 它也可以使用数字作为变量，但不能使用字符串。 这是为什么？

Answer 1

这个：

  execute immediate 'CREATE or replace VIEW interm2 AS
  SELECT AR_ID, kurs,
    ((TO_CHAR(to_date(di.kursdatum,''dd.mm.yyyy''),''YYYYMMDD''))+    (TO_CHAR(to_date(di.verfall,''dd.mm.yyyy''),''YYYYMMDD''))) AS dumdate
  FROM daten_import di 
  where di.AR_ID = '||instr||''; 

应该：

  execute immediate 'CREATE or replace VIEW interm2 AS
  SELECT AR_ID, kurs,
    ((TO_CHAR(to_date(di.kursdatum,''dd.mm.yyyy''),''YYYYMMDD''))+    (TO_CHAR(to_date(di.verfall,''dd.mm.yyyy''),''YYYYMMDD''))) AS dumdate
  FROM daten_import di 
  where di.AR_ID = '||instr; 

如果instr是一个整数，我认为是。

Answer 2

您连接instr的方式存在问题。 为了清楚起见，让我简化您的问题：

EXECUTE IMMEDIATE
  'CREATE OR REPLACE VIEW interm2 AS
   SELECT ar_id FROM daten_import di
   WHERE di.ar_id = ' || instr;

instr是一个字符串。 您需要在其周围加上引号。

EXECUTE IMMEDIATE
  'CREATE OR REPLACE VIEW interm2 AS
   SELECT ar_id FROM daten_import di
   WHERE di.ar_id = ''' || instr || '''';
--                  ^^               ^^
--                  ||               ||
--                  -- escaped quotes--