MySQ练习

Posted 2021-03-07 may18

表名称比较长时，可以通过别名简化

SELECT c.orderTime,c.shishou,c.totalPrice,c.cid=1164 FROM cash_order c WHERE c.cid=1164

FROM  cash_order c 即设置表cash_order的别名为c

如果有多个条件，用AND 连接

SELECT c.orderTime,c.shishou,c.totalPrice,c.cid=1164 FROM cash_order c WHERE c.cid=1164 AND c.totalPrice<5 and c.totalPrice>=1

排序时，用ORDER BY，默认是升序（ASC），如果要倒序显示，加DESC

SELECT c.orderTime,c.shishou,c.totalPrice,c.cid=1164 FROM cash_order c WHERE c.cid=1164 AND c.totalPrice<5 and c.totalPrice>=1 ORDER BY c.totalPrice DESC

限制查询的数量，用关键字LIMIT

SELECT c.orderTime,c.shishou,c.totalPrice,c.cid=1164 FROM cash_order c WHERE c.cid=1164 AND c.totalPrice<5 and c.totalPrice>=1 ORDER BY c.totalPrice DESC LIMIT 10

查询结果如下：