I'm asking about the possibility of indexing portions of a column's value where the column has a static field format. Example, a char(8) which contains all hex values (basically a hex number that's always 8 chars wide, leading zeros if needed). Someone might want to select all recs where the first 2 digits are 'ff' or maybe the last 4 hex digits match regexp_match '00[cdef]{2}' or maybe a match of the entire string... "0dd63a87".
If I know the placement and width of the fields that need to be indexed, can indices be defined to facilitate queries ? Example...
- match all 8 chars
- match the 3rd and 4th chars
- match the last 4 chars
I suppose I could fragment the thing into multiple columns for the purposes of a search. So add a column called "last4" as a char(4) that matches the last 4 chars of that column. Then index that. etc... But inquiring to see if there is something more elegant.
Just curious why not store it as a HEX string (functional index, even). And allow searching against the stringified hex, then your regex works?
