[postgis-users] Rounding up timestamps in postgresql

[tasneem dewaswala]

Hello,

I have a table consisting of following columns and data

*Msg_count     Latitude         Longitude             Utc_Time*
16              56.6650356667  12.8772211667         142640
24              56.6650415       12.8772395               142640.25
35              56.6650475       12.8772581667          142640.5
26              56.665053         12.8772778333          142640.75
23              56.6650593333  12.8772976667          142641
26              56.6650656667  12.8773183333          142641.25
25              56.665072         12.8773388333          142641.5
15              56.6650785       12.8773598333           142641.75

i need to find out sum of messages transmitted every second.
For eg. when i group (142640, 142640.25, 142640.5, 142640.75) it makes 1
sec and total number of messages sent during this interval are
16+24+35+26=101

I don't know how can do this using a query.

Does anyone have suggestion

Regards..
Tasha
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