SQL Server 索引维护sql语句

数据库 发布日期:2024/9/24 浏览次数:1

正在浏览:SQL Server 索引维护sql语句
使用以下脚本查看数据库索引碎片的大小情况:
复制代码 代码如下:
DBCC SHOWCONTIG WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS

以下使用脚本来处理维护作业:
复制代码 代码如下:
/*Perform a 'USE <database name>' to select the database in which to run the script.*/
-- Declare variables
SET NOCOUNT ON;
DECLARE @tablename varchar(255);
DECLARE @execstr varchar(400);
DECLARE @objectid int;
Declare @IndexName varchar(500);
DECLARE @indexid int;
DECLARE @frag decimal;
DECLARE @maxfrag decimal;
DECLARE @TmpName varchar(500);

-- Declare @TmpName =''
set @TmpName = ''

-- Decide on the maximum fragmentation to allow for.
SELECT @maxfrag = 30.0;

-- Declare a cursor.
DECLARE tables CURSOR FOR
SELECT TABLE_SCHEMA + '.' + TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE';

-- Create the table.
CREATE TABLE #fraglist (
ObjectName char(255),
ObjectId int,
IndexName char(255),
IndexId int,
Lvl int,
CountPages int,
CountRows int,
MinRecSize int,
MaxRecSize int,
AvgRecSize int,
ForRecCount int,
Extents int,
ExtentSwitches int,
AvgFreeBytes int,
AvgPageDensity int,
ScanDensity decimal,
BestCount int,
ActualCount int,
LogicalFrag decimal,
ExtentFrag decimal);

-- Open the cursor.
OPEN tables;

-- Loop through all the tables in the database.
FETCH NEXT
FROM tables
INTO @tablename;

WHILE @@FETCH_STATUS = 0
BEGIN;
-- Do the showcontig of all indexes of the table
INSERT INTO #fraglist
EXEC ('DBCC SHOWCONTIG (''' + @tablename + ''')
WITH FAST, TABLERESULTS, ALL_INDEXES, NO_INFOMSGS');
FETCH NEXT
FROM tables
INTO @tablename;
END;

-- Close and deallocate the cursor.
CLOSE tables;
DEALLOCATE tables;

-- Declare the cursor for the list of indexes to be defragged.
DECLARE indexes CURSOR FOR
SELECT ObjectName, ObjectId,IndexName,IndexId, LogicalFrag
FROM #fraglist
WHERE INDEXPROPERTY (ObjectId, IndexName, 'IndexDepth') > 0;

-- Open the cursor.
OPEN indexes;

-- Loop through the indexes.
FETCH NEXT
FROM indexes
INTO @tablename, @objectid, @IndexName,@indexid, @frag;


WHILE @@FETCH_STATUS = 0
BEGIN;
if @frag < @maxfrag
Begin
SELECT @execstr = 'ALTER INDEX [' + RTRIM(@IndexName) + '] ON [' + RTRIM(@tablename) + '] REORGANIZE WITH ( LOB_COMPACTION = ON ) '
print @maxfrag + ' ' + @execstr
End
else
Begin
SELECT @execstr = 'ALTER INDEX [' + RTRIM(@IndexName) + '] ON [' + RTRIM(@tablename) + '] REBUILD WITH ( PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, SORT_IN_TEMPDB = OFF, ONLINE = OFF )'
print @maxfrag + ' ' + @execstr
End

EXEC (@execstr);

--更新统计信息
IF @TmpName<>@tablename
BEGIN
SET @tmpName=@tableName
PRINT 'UPDATE STATISTICS '+@TableName + ' WITH FULLSCAN '
EXEC ('UPDATE STATISTICS '+@TableName + ' WITH FULLSCAN ')
END


FETCH NEXT
FROM indexes
INTO @tablename, @objectid, @IndexName,@indexid, @frag;
END;

-- Close and deallocate the cursor.
CLOSE indexes;
DEALLOCATE indexes;

-- Delete the temporary table.
DROP TABLE #fraglist;
GO
一文看懂荣耀MagicBook Pro 16
荣耀猎人回归!七大亮点看懂不只是轻薄本,更是游戏本的MagicBook Pro 16.
人们对于笔记本电脑有一个固有印象:要么轻薄但性能一般,要么性能强劲但笨重臃肿。然而,今年荣耀新推出的MagicBook Pro 16刷新了人们的认知——发布会上,荣耀宣布猎人游戏本正式回归,称其继承了荣耀 HUNTER 基因,并自信地为其打出“轻薄本,更是游戏本”的口号。
众所周知,寻求轻薄本的用户普遍更看重便携性、外观造型、静谧性和打字办公等用机体验,而寻求游戏本的用户则普遍更看重硬件配置、性能释放等硬核指标。把两个看似难以相干的产品融合到一起,我们不禁对它产生了强烈的好奇:作为代表荣耀猎人游戏本的跨界新物种,它究竟做了哪些平衡以兼顾不同人群的各类需求呢?