oracle常用命令

1. 表信息：

   SELECT tabCols.COLUMN_NAME AS "Field",
          tabCols.DATA_TYPE || '(' || tabCols.DATA_LENGTH || ')' AS "Type",
          cons.constraint_type as "Key",
          tabCols.NULLABLE AS "Null",
          colcomments.comments AS "Comment"
     FROM USER_TAB_COLS tabCols
    inner JOIN user_col_comments colcomments
       ON colcomments.TABLE_NAME = tabCols.TABLE_NAME
      AND colcomments.COLUMN_NAME = tabCols.COLUMN_NAME
     left JOIN user_cons_columns conscols
       on conscols.TABLE_NAME = tabCols.TABLE_NAME
      AND conscols.COLUMN_NAME = tabCols.COLUMN_NAME
     left join user_constraints cons
       ON cons.constraint_name = conscols.constraint_name
    where tabCols.TABLE_NAME = 'TBTEST'