I have two tables called 'data' and 'year'. The table 'data' has two
columns namely 'year' and 'value'. And table 'year' contains only one column
Table 'year' contains six rows always - they are current year, current
year + 1, ... current year + 5.
For example, if the current year is 2002, the table 'year' will have six rows as:
Table 'data' may or may not have all these years. In case one of these years is missing, I would like to see a row with a value 0 for that row. So I wrote a outer join query as follows:
SELECT nvl(sum(value),0) value, YEAR.year year FROM DATA,YEAR WHERE DATA.year(+)= YEAR.year GROUP BY YEAR.yearI want to know, if there is any other way by which I can write a query to produce the same result, but can avoid using 'year' table. Since I will always know the six years for which I want data from 'data' table. If one of them is missing, I want that year with a value 0 in the result.
You can write the query like this:
SELECT nvl(sum(data.value),0) value, Y.year year FROM DATA ,(select 2002 as year from dual union all select 2003 as year from dual union all select 2004 as year from dual union all select 2005 as year from dual union all select 2006 as year from dual union all select 2007 as year from dual) y WHERE DATA.year(+)= Y.year GROUP BY Y.year ;Usage of year table is eliminated if you know all values you can use a derived table that "builds" the in-line result set online and use it in the query.
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This was first published in April 2002