inserting one table data to other table already have

Question

I have two tables,mycode and mycode1

The two tables contain same field CODE and img.  I need to insert  the table2 to table 1 two tables. Both of them contain the same code numbers in CODE field.

 eg:  table 1

        CODE            img

        110               null

        111               null

        112               image3.jpg

table 2

        CODE            img

        110               imag1.jpg

        111               image2.jpg

 

I need the output as 

   table2

       CODE           img

        110               imag1.jpg

        111               image2.jpg

        112               image3.jpg