James,
James Kufrovich wrote:
>
> Hi.
>
> I'd like to check for the existence of data in a row of a database
> (MySQL), if given the value of a primary key. ("Is there already a row in
> the database that has this value as a key?") I don't care what data is in
> the row, or if more than one row (!!) is found. I'd hope that whatever
> method I use will stop searching the database after it finds the first
> match.
If it is a Primary Key then there there will be at most one row with
that value in the table.
>
> What would be the best way to go about this? Is there a special
> method that can do this, or would I have to use selectrow_array (or
> fetchrow_array or one of those) and then see if it finds anything? I
> suppose I can call 'finish' as soon as a match is found, if the method (or
> whatever) doesn't stop by itself. I'd appreciate any tips. Thanks.
Try
"select count(*) from fred where primaryKey = 'bert'"
as the query
I'm don't know how MySQL handles primary keys but other databases put a
Unique index on the column. The SQL above _should_ just look at the
index (or you could find the index name and use that in the query).
--MarkT
