Split a column of strings and enumerate them

Community Support
1

I have a table that has a column of type string with a max width of 4.  I want to split that string up into four separate columns representing each character and then enumerate them so that queries against the table are faster.  So for example,

t:(str:())

        str

0  | "T    "

1  | "  FT"

2  | "    C"

and I want

       str      | col1 | col2 | col3|

0  |   "T    " | T   |       |       |

1  |   " FT " |      |    F |   T  |

2  |   "    C" |      |       |    C |

When I do something like

select col1: str[0], col2:str[1], col3:str[2] from t

output looks like 

    col1 | col2 | col3

0 | T   |  F |  

1 |      |  T |

2 |

3 |            |   C

2

q)t:(str:(“T “;” FT”;" C"))

q)update col1: str[;0], col2:str[;1], col3:str[;2], col4:str[;3] from t

str col1 col2 col3 col4

--------------------------

"T " T

" FT" F T

" C" C

3

Works, thanks Tom

4

Actually I am having trouble casting this to a symbol.  And I would like to enumerate these columns.  

First of all, if I do 

update col1: $str[;0], col2:$str[;1], col3:$str[;2], col4:$str[;3] from t

it ends up the entire columns for each row, can I just cast that column to a symbol?

I need to cast to a symbol because I want to enumerate it, I can’t quite figure out how to enumerate a column, I know that .Q.en enumerates the sym column but if I want to have another enum from these four columns combined how would I do that?