Lets take a simple example of a DAY table (where NAME column is our 'type') :
NAME VALUE CREATION_DATE
-----------------------------------------------------------------
MORNING 90 2015-06-12
NOON 210 2015-06-12
EVENING 60 2015-06-12
MORNING 85 2015-06-13
NOON 240 2015-06-13
EVENING 50 2015-06-13
MORNING 92 2015-06-14
NOON 235 2015-06-14
EVENING 55 2015-06-14
We want to show DATE on x axis and series for MORNING, NOON, EVENING on y axis. To make this happen NextReports must obtain a query result like:
CREATION_DATE MORNING_V NOON_V EVENING_V
-------------------------------------------------------------------------------------------------
2015-06-12 90 210 60
2015-06-13 85 240 50
2015-06-14 92 235 55
Then it is very easy to add DATE on x axis and MORNING_V, NOON_V, EVENING_V on y axis as column series.
This transformation can be easily obtained using sub-queries. For example, on our table we will use following sql:
SELECT DISTINCT
a1.CREATIONDATE,
(select VALUE from DAY a2 where a2.name='MORNING' and
a2.CREATIONDATE=a1.CREATIONDATE) as MORNING_V,
(select VALUE from DAY a2 where a2.name='NOON' and
a2.CREATIONDATE=a1.CREATIONDATE) as NOON_V,
(select VALUE from DAY a2 where a2.name='EVENING' and
a2.CREATIONDATE=a1.CREATIONDATE) as EVENING_V
FROM
DAY a1
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