On Sep 30, 3:35 pm, "Paul Lautman" <paul.laut...@btinternet.com>
wrote:
> bill wrote:
> > I give this sql request:
> > $sql = "SELECT * FROM incoming_email order by 'status','serial' limit
> > 1 ";
>
> > where status is a 5 char varchar and serial is a mediumint and the
> > primary key.
>
> > There is an index
> > STATUS with no cardinality and fields: status, serial
>
> > The row returned is the one with the lower serial, but a higher status
>
> > eg serial status
> > 269 held
> > is returned instead of
> > 270 (status is blank)
>
> > How should the selection be written ?
>
> > bill
>
> Is status blank or is it NULL?


This is a good question. It is never defined in the insert, but the
structure says that the value may not be null but no default value is
given.
A quick select using phpMyAdmin for status = NULL returns no records
and one where status = '' (that is two single quotes) returns a
record, so I presume it is blank.