Activerecord::JDBCError: Invalid column number

Rails
1

Hi,

I’m rather new to Ruby and RoR, so I do not really know whether this ist
the right forum to place my question.

For my first ‘project’ I planned to create a simple online-viewer, which
grabs data from an existing database and make them visible in a
structured form via browsers. So I thought that could be the right
beginner-project, because I have only read datasets without any editing
or creating.

The existing database is a very old one (Pervasive 8.7) and the
db-design is poor, but that is all I have and I have to live with it.

Fortunately there are JDBC-Drivers, so a connection via
activerecord-jdbc-adapter will work… I thought.

Within the services of Netbeans using those JDBC-Drivers I’m able to
establish a connection to the database and the IDE shows me all
available tables and there referring datasets.

The content of database.yml is only:

development:
adapter: jdbc
username:
password:
driver: com.pervasive.jdbc.v2.Driver
url: jdbc:pervasive://192.168.0.130:1583/database

No test-db and no production-db, because the development-db is
read-only.

After putting these tow lines into the environment.rb:

$CLASSPATH << “file:///#{Rails.root}/lib/java/pvjdbc2.jar”
$CLASSPATH << “file:///#{Rails.root}/lib/java/pvjdbc2x.jar”

the application started with webrick gives no error-message, so I think,
that the JDBC-drivers are loaded correctly.

Now I made a model mandate_file.rb which contains

class MandateFile < ActiveRecord::Base

fix non-standard table and primary key name conventions

set_table_name “STAMM”
set_primary_key :D_LFDNR

fix the upper-cased named columns

    alias_attribute :id, :D_LFDNR

alias_attribute :annotext_az, :D_AZ
alias_attribute :name_creditor, :D_RUBGE

end

When I try to create a simple object via the console using “m =
MandateFile.new” I get the following list of errors:

ActiveRecord::JDBCError: Invalid column number
from arjdbc/jdbc/RubyJdbcConnection.java:121:in columns' from c:/jruby/lib/ruby/gems/1.8/gems/activerecord-jdbc-adapter-1.1.1/lib/arjdbc/jdbc/adapter.rb:229:injdbc_columns’
from
c:/jruby/lib/ruby/gems/1.8/gems/activerecord-3.0.7/lib/active_record/base.rb:680:in
columns' from c:/jruby/lib/ruby/gems/1.8/gems/activerecord-3.0.7/lib/active_record/persistence.rb:284:inattributes_from_column_definition’
from
c:/jruby/lib/ruby/gems/1.8/gems/activerecord-3.0.7/lib/active_record/locking/optimistic.rb:62:in
attributes_from_column_definition' from c:/jruby/lib/ruby/gems/1.8/gems/activerecord-3.0.7/lib/active_record/base.rb:1395:ininitialize’
from (irb):1:in evaluate' from org/jruby/RubyKernel.java:1088:ineval’
from C:/jruby/lib/ruby/1.8/irb.rb:158:in eval_input' from C:/jruby/lib/ruby/1.8/irb.rb:271:insignal_status’
from C:/jruby/lib/ruby/1.8/irb.rb:155:in eval_input' from org/jruby/RubyKernel.java:1418:inloop’
from org/jruby/RubyKernel.java:1191:in catch' from C:/jruby/lib/ruby/1.8/irb.rb:154:ineval_input’
from C:/jruby/lib/ruby/1.8/irb.rb:71:in start' from org/jruby/RubyKernel.java:1191:incatch’
from C:/jruby/lib/ruby/1.8/irb.rb:70:in start' from c:/jruby/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands/console.rb:44:instart’
from
c:/jruby/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands/console.rb:8:in
start' from c:/jruby/lib/ruby/gems/1.8/gems/railties-3.0.7/lib/rails/commands.rb:23:in(root)’
from org/jruby/RubyKernel.java:1038:in require' from script\rails:6:in(root)

I’ve googled for ‘Invalid column number’ but found nothing, what might
be helpful.

I think, that I make a very simple mistake, but I’ve no idea about it.
Are there any hints for me?

Thanks in advance!

Klaus

2

Sent from my iPhone

On May 7, 2011, at 2:51 PM, Klaus H. [email protected] wrote:

The content of database.yml is only:

Check to make sure your columns in your model are correctly listed. It
sounds like it is trying to use the id column or numerically increment a
column that is not numeric.

Also, if the database is read only then MandateFile.new is not going to
work anyway since you won’t be able to save the record.

B.

3

Okay, I’ve choesen an other table with only 11 columns and listed them
all:

class MandateFile < ActiveRecord::Base

fix non-standard table and primary key name conventions

set_table_name :AZLOELOG
set_primary_key :D_AZLOGNR

alias_attribute :id, :D_AZLOGNR
alias_attribute :anno_az, :D_AZLOAGAZ
alias_attribute :name_debtor, :D_AZLOGRUB1
alias_attribute :name_creditor, :D_AZLOGRUB2
alias_attribute :delete_date, :D_AZLOGDAT
alias_attribute :delete_user, :D_AZLOGUSER
alias_attribute :not_used, :D_AZLOGFREE
alias_attribute :log_sign, :D_AZLOGKE
alias_attribute :delete_year, :D_AZLOGAZJAHR
alias_attribute :delete_counter, :D_AZLOGAZZAEHL
alias_attribute :reserved, :D_AZLOGRES

end

I’ve also switched the database access to ‘read+write’. Column’s
D_AZLOGNR datatype is integer. IMHO I did and checked all that Bryan
told me, but the result is the same: ActiveRecord::JDBCError: Invalid
column number

Any mory suggestions?

4

On May 8, 3:36am, Klaus H. [email protected] wrote:

alias_attribute :annotext_az, :D_AZLOAGAZ
end

I’ve also switched the database access to ‘read+write’. Column’s
D_AZLOGNR datatype is integer. IMHO I did and checked all that Bryan
told me, but the result is the same: ActiveRecord::JDBCError: Invalid
column number

Any mory suggestions?

Do you get the same behavior if you just call ‘MandateFile.columns’? I
suspect you will - this sounds like an issue with the JDBC driver
rather than your code. You might want to try the AR-JDBC JIRA and/or
mailing lists:

http://kenai.com/jira/browse/ACTIVERECORD_JDBC

–Matt J.

5

Matt J. wrote in post #997376:

Do you get the same behavior if you just call ‘MandateFile.columns’?

Hi Matt,

MandateFile.columns quits with the same errormessage as you thought.

I suspect you will - this sounds like an issue with the JDBC driver
rather than your code.

Maybe, but if its so, it must be in addition to activerecord, because I
used the same JDBC driver several months ago to establish a connection
through pure Java and I was able to query the database via simple
SQL-Statements.

You might want to try the AR-JDBC JIRA and/or
mailing lists:

http://kenai.com/jira/browse/ACTIVERECORD_JDBC

Thanks, I will take a look at these.

Greetings

Klaus