ActiveRecordで全てのtable nameと全てのcolumn nameを得る

Get all table names

code:ruby

# <= 5.2

ApplicationRecord.connection.tables

# 5.2 <

ActiveRecord::Base.connection.tables

Get all columns of a table

code:ruby

ApplicationRecord.connection.columns('users').map(&:name)

ActiveRecord::Base.connection.columns('users').map(&:name)

# columns が返すのは Array<ActiveRecord::ConnectionAdapters::PostgreSQLColumn> のようなオブジェクト (PostgreSQLの場合)

# または以下

User.column_names

Get all columns of all tables

code:ruby

csv = CSV.generate(col_sep: "\t") do |csv|

ActiveRecord::Base.connection.tables.sort.each do |table_name|

ActiveRecord::Base.connection.columns(table_name).each do |column|

end

end

end

参考