Class: Pgerd::Database

Inherits:
Object
  • Object
show all
Defined in:
lib/pgerd/database.rb

Constant Summary collapse

TABLES_TO_IGNORE = 
%w(ar_internal_metadata schema_migrations)

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name) ⇒ Database

Returns a new instance of Database.



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# File 'lib/pgerd/database.rb', line 10

def initialize(name)
  @name = name
end

Instance Attribute Details

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/pgerd/database.rb', line 7

def name
  @name
end

Instance Method Details

#all_table_names ⇒ Object 



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# File 'lib/pgerd/database.rb', line 14

def all_table_names
  connection
    .query("SELECT tablename FROM pg_catalog.pg_tables")
    .map { |table| table['tablename'] }
    .reject { |name| name.start_with?('pg_') || name.start_with?('sql_')}
end

#all_view_names ⇒ Object 



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# File 'lib/pgerd/database.rb', line 21

def all_view_names
  connection
    .query("SELECT viewname FROM pg_catalog.pg_views WHERE schemaname NOT IN ('pg_catalog', 'information_schema')")
    .map { |view| view['viewname'] }
    .reject { |name| name.start_with?('pg_') || name.start_with?('sql_')}
end

#connection ⇒ Object 



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# File 'lib/pgerd/database.rb', line 71

def connection
  @connection ||= PG.connect(dbname: name)
end

#foreign_keys ⇒ Object 



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# File 'lib/pgerd/database.rb', line 28

def foreign_keys
  @foreign_keys ||= raw_foreign_keys.map { |data| ForeignKey.new(data) }
end

#raw_foreign_keys ⇒ Object 



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# File 'lib/pgerd/database.rb', line 32

def raw_foreign_keys
  connection
    .query "        select c.constraint_name\n            , x.table_schema as from_schema\n            , x.table_name as from_table\n            , x.column_name as from_column\n            , y.table_schema as to_schema\n            , y.table_name as to_table\n            , y.column_name as to_column\n        from information_schema.referential_constraints c\n        join information_schema.key_column_usage x\n            on x.constraint_name = c.constraint_name\n        join information_schema.key_column_usage y\n            on y.ordinal_position = x.position_in_unique_constraint\n            and y.constraint_name = c.unique_constraint_name\n        order by c.constraint_name, x.ordinal_position\n      END_SQL\nend\n"

#table_names ⇒ Object 



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# File 'lib/pgerd/database.rb', line 52

def table_names
  all_table_names - TABLES_TO_IGNORE
end

#tables ⇒ Object 



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# File 'lib/pgerd/database.rb', line 56

def tables
  @tables ||=
  table_names
    .map { |name| Table.new(self, name) }
    .sort_by { |table| table.foreign_keys.size }
    .reverse
end

#views ⇒ Object 



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# File 'lib/pgerd/database.rb', line 64

def views
  @views ||=
    all_view_names
    .map { |name| View.new(self, name) }
    .reverse
end