How return multiple lines in JFreechart dataset using MySQL and Java -

i created graph single line, connection database show below.

i used dataset returns data of query. need display more lines create thought in various datasets don't know how can implement or if possible.

i've seen examples of graph multiple lines, none helped me in wanted, return values ​​from database.

string query="select date,tempfrom records idsensor 'sensor1'"; jdbccategorydataset dataset = new jdbccategorydataset(criaconexao.getconexao(),         query); jfreechart chart = chartfactory.createlinechart("records", "date", "temp",          dataset, plotorientation.vertical, false, true, true); barrenderer renderer = null; categoryplot plot= null; renderer=new barrenderer(); chartframe frame = new chartframe("records", chart); frame.setvisible(true); frame.setsize(400,650); 

from javadoc of jdbccategorydataset:

the sql query must return @ least 2 columns. first column category name , remaining columns values (each column represents series). subsequent calls executequery(string) refresh dataset.

so in case should add columns query:

string query = "select date, value1, value2, value3, value4 records " +                "idsensor 'sensor1'"; 

you can subselects in sql well:

string query = "select date, value1, (select value2 table2 " +                "records.date = table2.date), value3, value4 records " +                "idsensor 'sensor1'"; 

if doesn't give enough flexibility, go next advice javadoc:

note: many people have found class restrictive in general use. greatest flexibility, please consider writing own code read data resultset , populate defaultcategorydataset directly.

--- update ---

you can auto-join (join table against itself) turn rows columns, or can write own code read data resultset. 1 possible way auto-join:

select r.date, r1.tempfrom, r2.tempfrom, r3.tempfrom records r, records r1, records r2, records r3 r.date = r1.date , r.date = r2.date , r1.date = r3.date ,       r1.idsensor = 'sensor1' , r2.idsensor = 'sensor2' , r3.idsensor = 'sensor3'; 

if possible 1 of idsensors, don't have tempfrom on date, need outer join. depends bit on database how write outer join couldn't include that. try first , see if helps you.