在查询时,可以为表和字段取一个别名。这个别名可以代替其指定的表和字段
为表取别名
mysql> SELECT * FROM department d -> WHERE d.d_id=1001; +------+-----------+--------------+-------------+ | d_id | d_name | function | address | +------+-----------+--------------+-------------+ | 1001 | 科技部 | 研发产品 | 3号楼5层 | +------+-----------+--------------+-------------+ row in set (0.00 sec)
这里为department表取了一个别名为d
为字段取别名
mysql> SELECT d_id AS department_id, d_name AS department_name -> FROM department; +---------------+-----------------+ | department_id | department_name | +---------------+-----------------+ | 1001 | 科技部 | | 1002 | 生产部 | | 1003 | 销售部 | +---------------+-----------------+ rows in set (0.00 sec)
此处语法与上面类似,只不过加了AS
时间: 2024-10-10 04:38:38