Using table_name_prefix with hyphen causes MySQL error

[bostrom]

Using Rails 3.0.10 with a table name prefix that includes a hyphen. This is set up in the model class like

    def self.table_name_prefix
      'my-db.'
    end

which works perfectly fine under certain circumstances. However, when ActiveRecord (or more correctly the MySQL adapter) constructs the sql for a query with, for example, an order by statement, it doesn't quote the prefix with backticks, which makes MySQL choke on the query.

    >> Campaign.last
    ActiveRecord::StatementInvalid: Mysql::Error: Unknown column 'my' in 'order clause': SELECT  `my-db`.`campaigns`.* FROM `my-db`.`campaigns` ORDER BY my-db.campaigns.id DESC LIMIT 1

    >> Campaign.inspect
    ActiveRecord::StatementInvalid: Mysql::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '-db' at line 1: SHOW TABLES IN my-db

Note the unquoted my-db in the queries.

A possible partial fix for this would be to add

        name = quote_table_name(name) if name
        database = quote_table_name(database) if database

to the tables method of mysql_adapter.rb, like so:

      def tables(name = nil, database = nil) #:nodoc:
        tables = []
        name = quote_table_name(name) if name
        database = quote_table_name(database) if database
        result = execute(["SHOW TABLES", database].compact.join(' IN '), name)
        result.each { |field| tables << field[0] }
        result.free
        tables
      end

[kennyj]

Hi! @bostrom
I've attemted to fix it. and I think that fixed it. Same to your way :)
Please test it !

[kennyj]

Anyway, I sent PR :)

[bostrom]

Thanks for the fix! But actually I solved it another way (probably the right way). I figured that using another database by prefixing the table name with the database name isn't the right way to go. Instead I defined the other database in config/database.yml and used establish_connection in the model instead.

But this fix might be relevant in other cases also, so a PR is probably not a bad idea anyways.