為了整理複雜的系統資料表結構，方便以後研發人員工作，特此整理資料字典。

oracle表結構涉及到幾個關鍵的系統表：

• cols –系統表
  

• user_col_comments –表名、列名、說明
  

• user_tab_comments –表名、型別、說明
  

• user_objects – 字典表檢視
  

真正匯出的SQL語句整理如下：

SELECT t1.Table_Name || chr(13) || t3.comments       AS "表名稱及說明",
       --t3.comments                                 AS
 
 "表說明",
       t1.Column_Name                                AS "欄位名稱",
       t1.DATA_TYPE || '(' || t1.DATA_LENGTH || ')'  AS "資料型別",
       t1.NullAble                                   AS "是否為空",
       t2.Comments                                   AS "欄位說明",
       t1.Data_Default "預設值"
       --t4.created                                  AS
 
 "建表時間"
  FROM cols t1
  LEFT JOIN user_col_comments t2 
         ON t1.Table_name = t2.Table_name
        AND t1.Column_Name = t2.Column_Name
  LEFT JOIN user_tab_comments t3 
         ON t1.Table_name = t3.Table_name
  LEFT JOIN user_objects t4 
         ON t1.table_name = t4.OBJECT_NAME
  WHERE NOT
 
 EXISTS (SELECT t4.Object_Name
          FROM User_objects t4
         WHERE t4.Object_Type = 'TABLE'
           AND t4.Temporary = 'Y'
           AND t4.Object_Name = t1.Table_Name)
  ORDER BY t1.Table_Name, t1.Column_ID;

直接將結果匯出至Excel檔案即可。