From: Michael Neumann <mneumann@...>
Date: 2003-10-13T00:08:26+09:00
Subject: Re: mysql_num_rows equivalent for DBI?

On Sun, Oct 12, 2003 at 05:17:19AM +0900, Ben Giddings wrote:
> paul vudmaska wrote:
> >What i think you are looking for is recordset#rows -
> >Returns the RPC (Row Processed Count) of the last
> >executed statement, or nil if no such exists.
> 
> That's what I thought I should be using, but it is always zero:
> 
> irb(main):097:0> dbh.execute("SELECT Username FROM Users").fetch_all
> [["ben"], ["harry"]]
> irb(main):098:0> dbh.execute("SELECT Username FROM Users").rows
> 0

Try this one:

  dbh.execute("SELECT Username FROM Users")['pg_row_count']

This is a Postgres-specific function, but should return what you except.

Alternatively you can always use SELECT COUNT(Username).

> irb(main):099:0> sth = dbh.prepare("SELECT Username FROM Users")
> ...
> irb(main):100:0> sth.execute
> [nil]
> irb(main):101:0> sth.rows
> 0
> irb(main):102:0> sth.fetch_all
> [["ben"], ["harry"]]
> 
> This appears to be a bug, doesn't it?

What exactly should be a bug? That sth.execute returns [nil]?  
That's not a bug, but even so should be changed to nil or self.

Regards,

  Michael