SQL SERVER 2008 R2 重建索引的方法
时间:2014-12-13 16:01 来源:linux.it.net.cn 作者:IT
项目升级数据库由SQL2000升级到2008R2,今天对数据库表进行碎片扫描,发现有些表碎片较大,于是决定重建索引,MSDN联机帮助是最好的老师,将相关脚本摘录备后查
参考sys.dm_db_index_physical_stats
检查索引碎片情况
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1.
SELECT
2.OBJECT_NAME(object_id)
as
objectname,
3.object_id
AS
objectid,
4.index_id
AS
indexid,
5.partition_number
AS
partitionnum,
6.avg_fragmentation_in_percent
AS
fra
7.
FROM
sys.dm_db_index_physical_stats (DB_ID(),
NULL
,
NULL
,
NULL
, ‘LIMITED
')
8.WHERE avg_fragmentation_in_percent > 10.0 AND index_id > 0;
9.
10.使用脚本中的 sys.dm_db_index_physical_stats 重新生成或重新组织索引 (来源于联机帮助)
11.
12.SET NOCOUNT ON;
13.DECLARE @objectid int;
14.DECLARE @indexid int;
15.DECLARE @partitioncount bigint;
16.DECLARE @schemaname nvarchar(130);
17.DECLARE @objectname nvarchar(130);
18.DECLARE @indexname nvarchar(130);
19.DECLARE @partitionnum bigint;
20.DECLARE @partitions bigint;
21.DECLARE @frag float;
22.DECLARE @command nvarchar(4000);
23.– Conditionally select tables and indexes from the sys.dm_db_index_physical_stats function
24.– and convert object and index IDs to names.
25.SELECT
26.object_id AS objectid,
27.index_id AS indexid,
28.partition_number AS partitionnum,
29.avg_fragmentation_in_percent AS frag
30.INTO #work_to_do
31.FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL , NULL, ‘LIMITED'
)
32.
WHERE
avg_fragmentation_in_percent > 10.0
AND
index_id > 0;
33.–
Declare
the
cursor
for
the list
of
partitions
to
be processed.
34.
DECLARE
partitions
CURSOR
FOR
SELECT
*
FROM
#work_to_do;
35.–
Open
the
cursor
.
36.
OPEN
partitions;
37.– Loop through the partitions.
38.WHILE (1=1)
39.
BEGIN
;
40.
FETCH
NEXT
41.
FROM
partitions
42.
INTO
@objectid, @indexid, @partitionnum, @frag;
43.IF @@FETCH_STATUS < 0 BREAK;
44.
SELECT
@objectname = QUOTENAME(o.
name
), @schemaname = QUOTENAME(s.
name
)
45.
FROM
sys.objects
AS
o
46.
JOIN
sys.schemas
as
s
ON
s.schema_id = o.schema_id
47.
WHERE
o.object_id = @objectid;
48.
SELECT
@indexname = QUOTENAME(
name
)
49.
FROM
sys.indexes
50.
WHERE
object_id = @objectid
AND
index_id = @indexid;
51.
SELECT
@partitioncount =
count
(*)
52.
FROM
sys.partitions
53.
WHERE
object_id = @objectid
AND
index_id = @indexid;
54.– 30
is
an arbitrary decision point
at
which
to
switch
between
reorganizing
and
rebuilding.
55.IF @frag < 30.0
56.
SET
@command = N‘
ALTER
INDEX
‘ + @indexname + N‘
ON
‘ + @schemaname + N‘.
' + @objectname + N‘ REORGANIZE'
;
57.IF @frag >= 30.0
58.
SET
@command = N‘
ALTER
INDEX
‘ + @indexname + N‘
ON
‘ + @schemaname + N‘.
' + @objectname + N‘ REBUILD'
;
59.IF @partitioncount > 1
60.
SET
@command = @command + N‘ PARTITION=' +
CAST
(@partitionnum
AS
nvarchar(10));
61.
EXEC
(@command);
62.PRINT N‘Executed: ‘ + @command;
63.
END
;
64.–
Close
and
deallocate
the
cursor
.
65.
CLOSE
partitions;
66.
DEALLOCATE
partitions;
67.–
Drop
the
temporary
table
.
68.
DROP
TABLE
#work_to_do;
69.GO
(责任编辑:IT)
项目升级数据库由SQL2000升级到2008R2,今天对数据库表进行碎片扫描,发现有些表碎片较大,于是决定重建索引,MSDN联机帮助是最好的老师,将相关脚本摘录备后查 参考sys.dm_db_index_physical_stats 检查索引碎片情况
(责任编辑:IT) |