Scattered vs Synchronised Data Sources

There are two ways that dates and times tend to be stored in databases.

They can be synchronised, meaning that every measurement is performed at the same effective time - for example, every point will be recorded every 10 seconds, and each point in that sample pass will have the same timestamp.

NameTimeSample
Channel A4:00:0012
Channel A4:00:1012.2
Channel A4:00:2012.4
Channel B4:00:004
Channel B4:00:105
Channel B4:00:206
Channel C4:00:003
Channel C4:00:102.8
Channel C4:00:202.6

Or they can be scattered, meaning that samples are taken at different times and time stamps are quite randomised.

NameTimeSample
Channel A3:59:1212
Channel B4:00:004
Channel B4:00:306
Channel C4:00:103
Channel C4:00:152.7

Database drivers support both kind of data source. However, synchronised data sources query significantly faster than scattered ones, because it is much more efficient to look up the previous sample time for one channel than it is to find the previous sample time for thousands.