我看有的是这样写的select g.name SUM(og.names_number) as names_number ;这个g.是什么意思,怎么还有个小数点啊,表中并没有g啊
回复讨论(解决方案)
. 前面的 q 表示表名或工作区(别名),你把指令贴全了
select g.id,g.name from table as g
g代表表的别名,如果表名很长可以通过别名来替代,
库名.表名.字段名
完整写是这样的
找一找整句中有没有as g的,如果有,g就是别名。g.name就是这个别名的数据中name字段。
例如
select g.name,c.name from table1 as g, table2 as c
如果没有,那么g有可能是数据库名
select g.name from table
哦是别名啊,那这个别名是怎么定义的呢,AS g吗?
as 可以缺省
select g.* from tbl_name as g
select g.* from tbl_name g
都是可以的
好的,谢谢,结贴了

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