module Sequel::MSSQL::DatabaseMethods

# File lib/sequel/adapters/shared/mssql.rb, line 38
def database_type
  :mssql
end

# File lib/sequel/adapters/shared/mssql.rb, line 49
def foreign_key_list(table, opts=OPTS)
  m = output_identifier_meth
  im = input_identifier_meth
  schema, table = schema_and_table(table)
  current_schema = m.call(get(Sequel.function('schema_name')))
  fk_action_map = FOREIGN_KEY_ACTION_MAP
  ds = metadata_dataset.from(:sys__foreign_keys___fk).
    join(:sys__foreign_key_columns___fkc, :constraint_object_id => :object_id).
    join(:sys__all_columns___pc, :object_id => :fkc__parent_object_id,     :column_id => :fkc__parent_column_id).
    join(:sys__all_columns___rc, :object_id => :fkc__referenced_object_id, :column_id => :fkc__referenced_column_id).
    where{{object_schema_name(:fk__parent_object_id) => im.call(schema || current_schema)}}.
    where{{object_name(:fk__parent_object_id) => im.call(table)}}.
    select{[:fk__name, 
            :fk__delete_referential_action, 
            :fk__update_referential_action, 
            :pc__name___column, 
            :rc__name___referenced_column, 
            object_schema_name(:fk__referenced_object_id).as(:schema), 
            object_name(:fk__referenced_object_id).as(:table)]}.
    order(:name, :fkc__constraint_column_id)
  h = {}
  ds.each do |row|
    if r = h[row[:name]]
      r[:columns] << m.call(row[:column])
      r[:key] << m.call(row[:referenced_column])
    else
      referenced_schema = m.call(row[:schema])
      referenced_table = m.call(row[:table])
      h[row[:name]] = { :name      => m.call(row[:name]), 
                        :table     => (referenced_schema == current_schema) ? referenced_table : Sequel.qualify(referenced_schema, referenced_table),
                        :columns   => [m.call(row[:column])], 
                        :key       => [m.call(row[:referenced_column])], 
                        :on_update => fk_action_map[row[:update_referential_action]], 
                        :on_delete => fk_action_map[row[:delete_referential_action]] }
    end
  end
  h.values
end

# File lib/sequel/adapters/shared/mssql.rb, line 43
def global_index_namespace?
  false
end

# File lib/sequel/adapters/shared/mssql.rb, line 89
def indexes(table, opts=OPTS)
  m = output_identifier_meth
  im = input_identifier_meth
  indexes = {}
  ds = metadata_dataset.from(:sys__tables___t).
   join(:sys__indexes___i, :object_id=>:object_id).
   join(:sys__index_columns___ic, :object_id=>:object_id, :index_id=>:index_id).
   join(:sys__columns___c, :object_id=>:object_id, :column_id=>:column_id).
   select(:i__name, :i__is_unique, :c__name___column).
   where{{t__name=>im.call(table)}}.
   where(:i__is_primary_key=>0, :i__is_disabled=>0).
   order(:i__name, :ic__index_column_id)

  if supports_partial_indexes?
    ds = ds.where(:i__has_filter=>0)
  end

  ds.each do |r|
    index = indexes[m.call(r[:name])] ||= {:columns=>[], :unique=>(r[:is_unique] && r[:is_unique]!=0)}
    index[:columns] << m.call(r[:column])
  end
  indexes
end

# File lib/sequel/adapters/shared/mssql.rb, line 28
def mssql_unicode_strings=(v)
  @mssql_unicode_strings = v
  reset_default_dataset
end

# File lib/sequel/adapters/shared/mssql.rb, line 115
def server_version(server=nil)
  return @server_version if @server_version
  @server_version = synchronize(server) do |conn|
    (conn.server_version rescue nil) if conn.respond_to?(:server_version)
  end
  unless @server_version
    m = SERVER_VERSION_RE.match(fetch(SERVER_VERSION_SQL).single_value.to_s)
    @server_version = (m[1].to_i * 1000000) + (m[2].to_i * 10000) + m[3].to_i
  end
  @server_version
end

# File lib/sequel/adapters/shared/mssql.rb, line 128
def supports_partial_indexes?
  dataset.send(:is_2008_or_later?)
end

# File lib/sequel/adapters/shared/mssql.rb, line 133
def supports_savepoints?
  true
end

# File lib/sequel/adapters/shared/mssql.rb, line 138
def supports_transaction_isolation_levels?
  true
end

# File lib/sequel/adapters/shared/mssql.rb, line 143
def supports_transactional_ddl?
  true
end

# File lib/sequel/adapters/shared/mssql.rb, line 149
def tables(opts=OPTS)
  information_schema_tables('BASE TABLE', opts)
end

# File lib/sequel/adapters/shared/mssql.rb, line 155
def views(opts=OPTS)
  information_schema_tables('VIEW', opts)
end