Truncate or Split

[#1]

I have a large dataset and I would like to split with the first 7 characters in a new column. I am trying to use the left function, but I am getting an error.

[#2]

try

left( char( :event_time ), 7 )

I am guessing that your event_time column is numeric

[#3]

or

for a 16 digit number this formula would give you the 7 left digits, where you can also use trunc instead of round ...

Round( :event_time / 1000000000 )