1.图例legend基础语法及用法
legend语法参数如下: matplotlib.pyplot.legend(*args, **kwargs)
Keyword
Descr iption
loc
Location code string, or tuple (see below).图例所有figure位置
prop
the font property字体参数
fontsize
the font size (used only if prop is not specifie
语法：Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger)
CREATE TRIGGER [ schema_name . ]trigger_name
ON { table | view }
[ WITH [ ,…n ] ]
{ FOR | AFTER | INSTEAD OF }
{ [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] }
[ W
