Mother of all unpivots - columns to rows?

Question

I have multiple tables as follows:
eventdate event1 event2 event3 event4 ... eventn
1/1/07 8 5 3 2 ... 7
2/1/07 1 14 6 9 ... 22
n/n
The tables have different column headers (apart from date), different numbers of columns and different numbers of rows.
I'd like to copy the data from these tables to one table as follows:
tablename eventname eventdate count
table1 event1 1/1/07 8
table1 event2 1/1/07 5
etc
Can anyone advise a solution? Something that handled one source table and could be set up to cycle through multiple tables via script would be great.
I have hit google and forums hard and seen a lot of solutions that either hard code column names or parse the contents of a delimited data column. This is not what I'm after.
Thanks in advance
user592258

Answer 1

Prior to 11g, unpivot goes like this:
SELECT id, column_value
FROM   your_table t1
     , TABLE(your_collection_type(col1,col2,col3,col4)) t2;which transforms
id, col1, col2, col3, col4into
id  column_value
id  column_value
id  column_value
id  column_valueIt gets a little more complicated if you have to generate a second column to show which source column the value was taken from. You would need an object type with two attributes and a collection of that type, and then use something like
SELECT id, t2.label, t2.val
FROM   your_table t1
     , TABLE(your_collection_type
       ( your_object_type(1,col1)
       , your_object_type(2,col2)
       , your_object_type(3,col3)
       , your_object_type(4,col4))
       ) t2;