How do I query a list in a field?

Question

I have a table of the form:

t                             p      s    c
----------------------------------------------------------
2019.08.06D13:29:45.746200000 4.5    4    (," ";,"T";,"I")
2019.08.06D13:29:58.413500000 4.5148 14   (," ";,"T";,"I")
2019.08.06D13:30:00.072000000 4.65   1522 (," ";,"O")
2019.08.06D13:30:03.681300000 4.5048 1    (," ";,"I")
2019.08.06D13:30:04.045200000 4.5    5    (," ";,"I")

I'm trying to grab the row at 13:00, that contains "O" in the column c.

I think it should be something like:

select from t where "O" in c

but it doesn't seem to work (null result). I've tried raze on this column too, but it doesn't help. What am I doing wrong?

Edit with raze each c:

2019.08.06D13:29:45.746200000 4.5    4    " TI"
2019.08.06D13:29:58.413500000 4.5148 14   " TI"
2019.08.06D13:30:00.072000000 4.65   1522 " O"
2019.08.06D13:30:03.681300000 4.5048 1    " I"
2019.08.06D13:30:04.045200000 4.5    5    " I"

Answer 1

Alternative approach for this simple example with index:

q)select from t where c[;1;0] = "O"
c
---------
," " ,"O"

Although likely this could be broken if you aren't looking for "O" to be the 2nd item in each list. Also note this only works with = because it gets down to a character instead of a string (which is a list of characters)