Mysql 在sql脚本中使用变量？

我有下面的mysql脚本，它获取几个表中的行总数并将它们相加。然后我想在下一步执行的另一个脚本中使用这个“Total”

我想显示计数占总数的百分比。很明显，由于未确认“总计”，以下内容不起作用。如何在下一条语句中使用第一条语句的结果

select (
(select count(*) from t1) +
(select count(*) from t2) +
(select count(*) from t3) +
(select count(*) from t4) +
(select count(*) from t5) +
(select count(*) from t6)) As Total;


select
round((count(greater10) / Total * 100),2) As greater10,
round((count(8to10) / Total * 100),2)  As 8to10,
round((count(6to8) / Total * 100),2) As 6to8,
round((count(4to6) / Total * 100),2) As 4to8,
round((count(2to4) / Total * 100),2) As 2to4,
round((count(halfto2) / Total * 100),2) As halfto2,
round((count(lesshalf)/ Total * 100),2) As lesshalf
from t7;

---

您可以使用语法将结果保存到文件中

只要会话保持活动状态，用户变量就会保持该值。因此，您可以在后续查询中使用该变量，只要它位于同一数据库连接中

另一个选项是将total查询作为子查询执行，以便它立即可用

select
round((count(greater10) / t.Total * 100),2) As greater10,
round((count(8to10) / t.Total * 100),2)  As 8to10,
round((count(6to8) / t.Total * 100),2) As 6to8,
round((count(4to6) / t.Total * 100),2) As 4to8,
round((count(2to4) / t.Total * 100),2) As 2to4,
round((count(halfto2) / t.Total * 100),2) As halfto2,
round((count(lesshalf)/ t.Total * 100),2) As lesshalf
from (
    select (
    (select count(*) from t1) +
    (select count(*) from t2) +
    (select count(*) from t3) +
    (select count(*) from t4) +
    (select count(*) from t5) +
    (select count(*) from t6)) AS Total)
) AS t,
t7;

---

谢谢-正是我想要的。很好！

select
round((count(greater10) / t.Total * 100),2) As greater10,
round((count(8to10) / t.Total * 100),2)  As 8to10,
round((count(6to8) / t.Total * 100),2) As 6to8,
round((count(4to6) / t.Total * 100),2) As 4to8,
round((count(2to4) / t.Total * 100),2) As 2to4,
round((count(halfto2) / t.Total * 100),2) As halfto2,
round((count(lesshalf)/ t.Total * 100),2) As lesshalf
from (
    select (
    (select count(*) from t1) +
    (select count(*) from t2) +
    (select count(*) from t3) +
    (select count(*) from t4) +
    (select count(*) from t5) +
    (select count(*) from t6)) AS Total)
) AS t,
t7;