A <BLOB literal> is the letter "X" (upper case mandatory) followed by a string
of zero or more hexits inside a pair of single quote marks. (A hexit is
either (a) any of the digits 0 through 9 or (b) any of the letters A
through F (upper case or lower case allowed) and is four bits long -- 0, 1, 2,
3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F are interpreted as 0000, 0001, 0010,
0011, 0100, 0101, 0110, 0111, 1000, 1001, 1010, 1011, 1100, 1101, 1110 and
1111, respectively.) Its <data type> is variable length BLOB.
The <literal>'s length is four times the number of hexits inside the quote
marks; the delimiting single quotes are not part of the <literal>, therefore
they are not included in the calculation of the <BLOB literal>'s size. Here are
some examples of <BLOB literal>s:
X'49FE' X'a31d'
[Obscure Rule] A long <BLOB literal> may be broken up into two or more smaller <BLOB literal>s, split by a <separator> that must include a newline character. When such a <literal> is encountered, your DBMS will ignore the <separator> and treat the multiple strings as a single <literal>. For example, these two <BLOB literal>s are equivalent:
X'49FE' 'A31D' X'49FEA31D'
(In the first example, there is a carriage return newline <separator> between
"FE'" and "'A3".)