Oracle数据库查询表结构

SELECT 
  tab_col.table_name AS "表名", 
  tab_cmt.comments AS "表说明", 
  tab_col.column_id AS "字段序号", 
  tab_col.column_name AS "字段名", 
  col_cmt.comments AS "字段说明", 
  tab_col.data_type AS "数据类型", 
  tab_col.data_length AS "数据长度", 
  tab_col.data_precision AS "整数位", 
  tab_col.data_scale AS "小数位" 
FROM 
  all_col_comments col_cmt, 
  all_tab_columns tab_col, 
  all_tab_comments tab_cmt 
WHERE 
  col_cmt.table_name IN (SELECT user_tab.table_name FROM user_all_tables user_tab) 
  AND col_cmt.OWNER = tab_col.OWNER 
  AND col_cmt.table_name = tab_col.table_name 
  AND col_cmt.column_name = tab_col.column_name 
  AND tab_cmt.table_name = col_cmt.table_name 
  AND tab_cmt.OWNER = col_cmt.OWNER 
  AND col_cmt.OWNER = '用户名' 
  AND tab_col.table_name = '表名' 
ORDER BY 
  tab_col.column_id;