st: expanding data set by variable

[KOTa <kota.alba@gmail.com>]

hi all,

i need help with creating from each observation with start and end
variables few several according to values of start and end i.e. to
split observations so there would be no partial (full overlap is ok)
time overlap between them, preserving all other variables the same

sample of data:

ID                start 	end	             user	type
1	  20071001	20071010	1	A
2	  20071003	20071231	1	A
3	  20071009	20080214	1	A
4	  20080117	20080117	1	B
5	  20070306	20070308	2	A
6	  20070314	20070319	2	A
7	  20070314	20070316	2	A

the result i need is (from first 4)

ID                start 	end	             user	type
1	  20071001	20071003	1	A
1	  20071003	20071009	1	A
1	  20071009	20071010	1	A
2	  20071003	20071009	1	A
2	  20071009	20071010	1	A
2	  20071010	20071231	1	A
3	  20071009	20071010	1	A
3	  20071010	20081231	1	A
3	  20071231	20080214	1	A
4	  20080117	20080117	1	B

i was think about counting how many overlaps there are for each
observation (i.e. 3 for ID 1) saving it into additional variable per
observation and then to use expand and replace start/end value.

but didn't find a way how to copy observation by variable value number of times


thank you in advance
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