Get all partition in MS SQL Server

DECLARE @TableName NVARCHAR(200) = N''

SELECT SCHEMA_NAME(o.schema_id) + '.' + OBJECT_NAME(i.object_id) AS [object]

     , p.partition_number AS [p#]

     , fg.name AS [filegroup]

     , p.rows

     , au.total_pages AS pages

     , CASE boundary_value_on_right

       WHEN 1 THEN 'less than'

       ELSE 'less than or equal to' END as comparison

     , rv.value

     , CONVERT (VARCHAR(6), CONVERT (INT, SUBSTRING (au.first_page, 6, 1) +

       SUBSTRING (au.first_page, 5, 1))) + ':' + CONVERT (VARCHAR(20),

       CONVERT (INT, SUBSTRING (au.first_page, 4, 1) +

       SUBSTRING (au.first_page, 3, 1) + SUBSTRING (au.first_page, 2, 1) +

       SUBSTRING (au.first_page, 1, 1))) AS first_page

FROM sys.partitions p

INNER JOIN sys.indexes i

     ON p.object_id = i.object_id

AND p.index_id = i.index_id

INNER JOIN sys.objects o

     ON p.object_id = o.object_id

INNER JOIN sys.system_internals_allocation_units au

     ON p.partition_id = au.container_id

INNER JOIN sys.partition_schemes ps

     ON ps.data_space_id = i.data_space_id

INNER JOIN sys.partition_functions f

     ON f.function_id = ps.function_id

INNER JOIN sys.destination_data_spaces dds

     ON dds.partition_scheme_id = ps.data_space_id

     AND dds.destination_id = p.partition_number

INNER JOIN sys.filegroups fg

     ON dds.data_space_id = fg.data_space_id

LEFT OUTER JOIN sys.partition_range_values rv

     ON f.function_id = rv.function_id

     AND p.partition_number = rv.boundary_id

WHERE i.index_id < 2

     AND o.object_id = OBJECT_ID(@TableName);

        select * from sys.partitions where object_id= 379864420

        select * from sys.system_internals_allocation_units