substr(RAW data)

[scottgai]

I have question like this:
suppose I create a table:

create table mytable(msg  raw(254));

and there is a record in this table which contains the following message like:

616C6D6B000000......

I want to retrieve the first character from table mytable, I use such a sql statement:

select substr(msg,1,4) from mytable

the result only return the first 2 character: 616C
If i use substr(mst,1,8), then i got what i want.

I was confused about 2 points:
1. what does the number '254' mean in its definition? it means 254 bytes or others?
2. why should substr recognize four bits of raw data as a unit(char)?

who can explain this?
thanks in advance!

Scott

insert into mytable('call')

 

[JamesGordon]

That it can store upto 254 bytes of data.
The substr is a character function so my guess is that it converts the raw to char and then gives you the first 4 characters.