TinyTds::Error: Type T_FK is not a defined system type.

[nPaul]

Rails version 6
multi database using

for example if run db:rollback
got error:

--trace log

** Invoke db:rollback (first_time)
** Invoke db:load_config (first_time)
** Invoke environment (first_time)
** Execute environment
** Execute db:load_config
** Execute db:rollback
== 20200810025414 AddDescriptionToOrders: reverting ===========================
-- remove_column(:orders, :description, :string)
   -> 0.0017s
== 20200810025414 AddDescriptionToOrders: reverted (0.0026s) ==================

** Invoke db:_dump (first_time)
** Execute db:_dump
** Invoke db:schema:dump (first_time)
** Invoke db:load_config 
** Execute db:schema:dump
rails aborted!
ActiveRecord::StatementInvalid: TinyTds::Error: Type T_FK is not a defined system type
```.

other databases is normal dumped after db:migration and db:rollback
this error got also if run
rails db:migrate:down:primary VERSION=123123123

i think sql adapter has bug on dumping command

[nPaul]

FREETDS version

tsql -C
Compile-time settings (established with the "configure" script)
                            Version: freetds v1.1.24
             freetds.conf directory: /usr/local/etc
     MS db-lib source compatibility: no
        Sybase binary compatibility: no
                      Thread safety: yes
                      iconv library: yes
                        TDS version: 7.3
                              iODBC: no
                           unixodbc: yes
              SSPI "trusted" logins: no
                           Kerberos: no
                            OpenSSL: yes
                             GnuTLS: no
                               MARS: yes

[defaultzero]

I'm having the exact issue. Were you able to solve this?

[defaultzero]

To be more helpful, this is caused by connecting to our ERP 2012 SQL Server DB.
It has many different custom column types. SiteType, being among them. All which cause the error,
TinyTds::Error: Type SiteType is not a defined system type.

It would be helpful to know how to pass custom system types to TinyTDS. Many of these are datatypes are glorified strings.

Is it possible to map, for instance, SiteType = String, somewhere, so that TinyTDS can handle?

[aidanharan]

There is an article about using custom data types in Rails with PostgreSQL https://pganalyze.com/blog/custom-postgres-data-types-ruby-rails

The same technique might work for the SQL Server adapter but I've never tried it myself.