Kazuya Togashi <togashi(at)sra(dot)co(dot)jp> writes:
> With version 7.3.4, following query returns true, but with version 7.4.2
> it returns false.
> select ' '::text = ' '::char;
Offhand that seems like a step forward to me. "char" type considers
trailing spaces to be insignificant, so it is really correct to consider
that ' '::char is equivalent to ''::text, not ' '::text which represents
a single significant space.
If you do not like this behavior, I suggest casting your text input to
char so that the comparison will occur under char rules not text rules.
regards, tom lane