Simplest way to query XML in MSSQL

For Accessing XML nodes:

DECLARE @xml xml
SET @xml = N'
         1002008-09-10
         1012008-09-11
       '
SELECT
doc.col.value('ponumber[1]', 'nvarchar(10)') ponumber
,doc.col.value('podate[1]', 'datetime') podate
FROM @xml.nodes('/polist/po') doc(col)

For Accessing element attributes:

DECLARE @xml xml
SET @xml = N'
         
         
       '
SELECT
doc.col.value('@ponumber', 'nvarchar(10)') ponumber
,doc.col.value('@podate', 'datetime') podate

FROM @xml.nodes('/polist/po') doc(col)

For accessing XML arrays:

DECLARE @xml xml
SET @xml = N'
         100
         101
       '
SELECT