oracle - SQL query to get current and last year sales -
    i have following table sales:   date        store   sales 1/1/2015    st01    12123 1/1/2015    st02    3123 1/1/2016    st01    4213 1/1/2016    st03    2134   when try self join year , last year sales closed store not showing up. result should this:   date        store   year sales   last year sales 1/1/2016    st01    4213              1212 1/1/2016    st02    0                 3123 1/1/2016    st03    2134              0   my query follows:   select cy.date,         cy.store cy.sales,         ly.sales    sales cy,         sales ly   cy.store(+) = ly.store(+)         , ly.date = cy.date - 365           oracle setup :   create table sales ( "date", store, sales ) select date '2015-01-01', 'st01', 12123 dual union select date '2015-01-01', 'st02',  3123 dual union select date '2016-01-01', 'st01',  4213 dual union select date '2016-01-01', 'st03',  2134 dual;   query :   select trunc( sysdate, 'yy' )...