MySQL在命令中添加日期对我不起作用

Question

1.查找在9月份完成的所有销售。2. saldate格式是年/月/日，命令中缺少最后一行吗？

select s.orderno "order number",sa.saledate "sale date", st.lastname "last 
name"
from sales s, sales sa, staff st
where s.orderno = sa.orderno and
sa.staffno = st.staffno and
sa.saledate = ????????;

Answer 1

您可以使用mysql函数 month 查找特定日期的月份，并使用STR_TO_DATE将字符串解析为日期：

select s.orderno ,sa.saledate , st.lastname 
from sales s, sales sa, staff st
where s.orderno = sa.orderno and
sa.staffno = st.staffno and
MONTH(sa.saledate) = 9

月份：http://www.w3resource.com/mysql/date-and-time-functions/mysql-month-function.php

STR_TO_DATE：http://www.w3resource.com/mysql/date-and-time-functions/mysql-str_to_date-function.php