From: M Mohr <messju@...>
Date: 2002-09-23T22:02:29+09:00
Subject: Re: mysql-ruby: MysqlField class: "type" instance method

Markus Jais <info@mjais.de> writes:

> hello
> I am writing a tutorial about mysql ruby and I have a question
> about the MysqlField class
> the method "type" returns the field type. in my examples
> it returns a number for example 253 for a field with type VARCHAR.
> 
> is it possible to get a more readable representation of this value??

the types are defined as constants of the MysqlField class. you can build
a lookup-table with something like

types = Hash.new
MysqlField.constants.each { |cname|
  cval = MysqlField.const_get(cname)
  if (cname =~ /^TYPE_/)    
    types[cval.to_i] = cname 
  end
}


after that you have a hash that maps the types to their
constant-names.  unfortunately the 253 for TYPE_VAR_STRING is not
defined in the mysql-extension. 

the reason for that could be:

(from http://www.mysql.com/doc/en/News-3.21.0.html)

"Changes in release 3.21.0

- For easier client code, the client should no longer use
   FIELD_TYPE_TINY_BLOB, FIELD_TYPE_MEDIUM_BLOB, FIELD_TYPE_LONG_BLOB
   or FIELD_TYPE_VAR_STRING (as previously returned by
   mysql_list_fields). You should instead only use FIELD_TYPE_BLOB or
   FIELD_TYPE_STRING. If you want exact types, you should use the
   command SHOW FIELDS."

so you should do m.query("SHOW FIELDS FROM table") instead of m.list_fields('table')
to get a more readable representation of your metadata, i guess.

have fun
messju

 
> markus