Query help

[DotNetGnat]

Hello All,

I have a table as shown below:

trackid    | beginAt | endAt
_____________________________
track1     |  0      | 1.55
track1     |  1.55   | 2.20
track1     |  2.20   | 3.25

track2     |  0      | 0.55
track2     |  1.05   | 1.80

track3     |  0      | 2.21
track3     |  2.15   | 2.80
track3     |  3.20   | 3.25

All tracks identified by trackid begin at 0 and can have number of segments and the end of the track is identified by the highest endAt number.

I want help with writing a query that identifies the breaks in the segments...for example...track1 is fine and has no problems and no breaks, ending point is the same as next beginning point...

but for track2 and track3 there are breaks as ending point is not same as the beginning point...

thanks in advance...

-DNG

 

[DotNetGnat]

i guess i have figured it out with a subquery...

thanks for looking...

-DNG

 

[Dagon]

I would have used LEAD() and LAG() functions.

 

[DotNetGnat]

thanks Dagon. I am definitely looking for other options...I am trying to come up with an efficient query since the table has millions of records...I am not sure how efficient is a subquery...

-DNG