--- /dev/null
+module ActiveRecord
+ module ConnectionAdapters
+ class PostgreSQLAdapter < AbstractAdapter
+
+ # This mightn't be in Core, but count(distinct x,y) doesn't work for me
+ def supports_count_distinct? #:nodoc:
+ false
+ end
+
+ def concat(*columns)
+ columns = columns.map { |c| "CAST(#{c} AS varchar)" }
+ "(#{columns.join('||')})"
+ end
+
+ # Executes an INSERT query and returns the new record's ID
+ def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil)
+ # Extract the table from the insert sql. Yuck.
+ table = sql.split(" ", 4)[2].gsub('"', '')
+
+ # Try an insert with 'returning id' if available (PG >= 8.2)
+ if supports_insert_with_returning?
+ pk, sequence_name = *pk_and_sequence_for(table) unless pk
+ if pk
+ quoted_pk = if pk.is_a?(Array)
+ pk.map { |col| quote_column_name(col) }.join(ID_SEP)
+ else
+ quote_column_name(pk)
+ end
+ id = select_value("#{sql} RETURNING #{quoted_pk}")
+ clear_query_cache
+ return id
+ end
+ end
+
+ # Otherwise, insert then grab last_insert_id.
+ if insert_id = super
+ insert_id
+ else
+ # If neither pk nor sequence name is given, look them up.
+ unless pk || sequence_name
+ pk, sequence_name = *pk_and_sequence_for(table)
+ end
+
+ # If a pk is given, fallback to default sequence name.
+ # Don't fetch last insert id for a table without a pk.
+ if pk && sequence_name ||= default_sequence_name(table, pk)
+ last_insert_id(table, sequence_name)
+ end
+ end
+ end
+ end
+ end
+end