T-SQL查询以获取索引碎片信息

Question

我一直在开发一个使用DMVs来获取索引碎片信息的查询。

但是，该查询提供了比预期更多的结果。我认为问题出在joins中。

有什么想法吗？

select distinct '['+DB_NAME(database_id)+']' as DatabaseName,
    '['+DB_NAME(database_id)+'].['+sch.name+'].['
    + OBJECT_NAME(ips.object_id)+']' as TableName,
    i.name as IndexName,
    ips.index_type_desc as IndexType,
    avg_fragmentation_in_percent as avg_fragmentation,
    SUM(row_count) as Rows
FROM
    sys.indexes i INNER JOIN
    sys.dm_db_index_physical_stats(NULL,NULL,NULL,NULL,'LIMITED') ips ON
        i.object_id = ips.object_id INNER JOIN
    sys.tables tbl ON tbl.object_id  = ips.object_id INNER JOIN
    sys.schemas sch ON sch.schema_id = tbl.schema_id INNER JOIN
    sys.dm_db_partition_stats ps ON ps.object_id = ips.object_id
WHERE
    avg_fragmentation_in_percent <> 0.0 AND ips.database_id = 6
    AND OBJECT_NAME(ips.object_id) not like '%sys%'
GROUP BY database_id, sch.name, ips.object_id, avg_fragmentation_in_percent,
    i.name, ips.index_type_desc
ORDER BY avg_fragmentation_in_percent desc

Answer 1

我认为你需要index_id来对抗sys.dm_db_partition_stats和sys.indexes。

使用sys.dm_db_index_physical_stats的第一个参数来过滤db可能比使用where子句ips.database_id = 6更好。

我不理解distinct、group by或sum(row_count)条款。

以下是一个查询，您可以尝试并查看它是否执行了您想要的操作。

select
  db_name(ips.database_id) as DataBaseName,
  object_name(ips.object_id) as ObjectName,
  sch.name as SchemaName,
  ind.name as IndexName,
  ips.index_type_desc,
  ps.row_count
from sys.dm_db_index_physical_stats(6,NULL,NULL,NULL,'LIMITED') as ips
  inner join sys.tables as tbl
    on ips.object_id = tbl.object_id
  inner join sys.schemas as sch
    on tbl.schema_id = sch.schema_id  
  inner join sys.indexes as ind
    on ips.index_id = ind.index_id and
       ips.object_id = ind.object_id
  inner join sys.dm_db_partition_stats as ps
    on ps.object_id = ips.object_id and
       ps.index_id = ips.index_id and
       ps.partition_number = ips.partition_number