Help with SQL?

What does the following programming example is the SQIJ (in Java)-in Figure 9.8, processing multiple tuples at a time, declaration of variables is given.) What does the program segment J2A do? What does line 0 do? What do lines (2 to 3) do? What do lines (4 to 1) do? What does line 9 do? What docs line 10 do? What do lines (11 to 12) do? What does line 13 do? What do lines (14 to 15) do? What is the purpose of the iterator in SQIJ On which linc(s)) and with what command is the named iterator declared? On which linc(s)) and with what command is the named iterator associated with a query; On which linc(s)) and with what command is the named iterator moved to the next row in the result of the query