Mysql Database Update Error Resolution _MYSQL

Statement:

UPDATESET Age=5WHERE ' name '=' mang '      

As the name implies is to change the age of Mang to 5, but the result is very helpless-

affect the number of rows is 0, what's going on, the grammar is correct, where there is no problem ah ...

Casually changed, the name of the two quotes removed, but the result was inadvertently successful-

But with the graphical interface changes, the results are even more confusing--

The generated code is-

UPDATESET='WHERE '= ' Mang '1 ;      

Baffled by the solution ...

By comparison, I found that the single quotes I wrote were not the same as the generated single quotes ...

All kinds of dizzy, various confused, all kinds of puzzled, in the end which is perfect???