Alex,
Seguindo na mesma linha de raciocínio apresentada pelo outro argumentador.
Você compartilhar com vocês dois exemplos de código, o primeiro vai identificar as Heap Tables existentes no seu banco de dados e o seguinte as taxas de fragmentação de cada tabela:
1 - Identificando as Heap Tables, com base, na junão entre as visões de catálogo de sistema
sys.indexes,
sys.tables e
sys.schemas:
SELECT SCH.name + '.' + TBL.name as TableName
from sys.indexes as IDX
inner join sys.tables as TBL on TBL.object_id = IDX.object_id
inner join sys.schemas as SCH on TBL.schema_id = SCH.schema_id
where IDX.type = 0 --> Heap
order by TableName;
2 - Identificando as taxas de fragmentação, elaborado com base na documentação oficial da DMV sys.dm_db_index_physical_stats e sys.indexes:
Select object_name(ddips.object_id) As 'Tabela',
si.name As 'Índice',
convert(decimal(5,2),isnull(ddips.avg_fragmentation_in_percent,0)) As '% Média de Fragmentação',
ddips.page_count As 'Páginas',
ddips.compressed_page_count As 'Páginas compactadas',
ddips.record_count As 'Registros',
ddips.ghost_record_count As 'Registros Fantasmas'
From sys.dm_db_index_physical_stats(db_id(), object_id('DigiteAquioNomedaSuaTabela'),null, null, 'detailed') ddips Inner Join sys.indexes si
on si.object_id = ddips.object_id
Where ddips.avg_fragmentation_in_percent > 0
Go
Este terceiro exemplo também extraído da documentação Oficial Microsoft relacionada a DMV: sys.dm_db_index_physical_stats
vai lhe ajudar a identificar as taxas de fragmentação e o mesmo possibilita executar o processo de Rebuild ou Reorganize de cada índice:
USE NomeDoSeuBancoDeDados
Go
SET NOCOUNT ON
Go
DECLARE @objectid int;
DECLARE @indexid int;
DECLARE @partitioncount bigint;
DECLARE @schemaname nvarchar(130);
DECLARE @objectname nvarchar(130);
DECLARE @indexname nvarchar(130);
DECLARE @partitionnum bigint;
DECLARE @partitions bigint;
DECLARE @frag float;
DECLARE @command nvarchar(4000);
-- Conditionally select tables and indexes from the sys.dm_db_index_physical_stats function
-- and convert object and index IDs to names.
SELECT
object_id AS objectid,
index_id AS indexid,
partition_number AS partitionnum,
avg_fragmentation_in_percent AS frag
INTO #work_to_do
FROM sys.dm_db_index_physical_stats (DB_ID(), NULL, NULL , NULL, 'LIMITED')
WHERE avg_fragmentation_in_percent > 10.0 AND index_id > 0;
-- Declare the cursor for the list of partitions to be processed.
DECLARE partitions CURSOR FOR SELECT * FROM #work_to_do;
-- Open the cursor.
OPEN partitions;
-- Loop through the partitions.
WHILE (1=1)
BEGIN;
FETCH NEXT
FROM partitions
INTO @objectid, @indexid, @partitionnum, @frag;
IF @@FETCH_STATUS < 0 BREAK;
SELECT @objectname = QUOTENAME(o.name), @schemaname = QUOTENAME(s.name)
FROM sys.objects AS o
JOIN sys.schemas as s ON s.schema_id = o.schema_id
WHERE o.object_id = @objectid;
SELECT @indexname = QUOTENAME(name)
FROM sys.indexes
WHERE object_id = @objectid AND index_id = @indexid;
SELECT @partitioncount = count (*)
FROM sys.partitions
WHERE object_id = @objectid AND index_id = @indexid;
-- 30 is an arbitrary decision point at which to switch between reorganizing and rebuilding.
IF @frag < 30.0
SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REORGANIZE';
IF @frag >= 30.0
SET @command = N'ALTER INDEX ' + @indexname + N' ON ' + @schemaname + N'.' + @objectname + N' REBUILD';
IF @partitioncount > 1
SET @command = @command + N' PARTITION=' + CAST(@partitionnum AS nvarchar(10));
EXEC (@command);
PRINT N'Executed: ' + @command;
END;
-- Close and deallocate the cursor.
CLOSE partitions;
DEALLOCATE partitions;
-- Drop the temporary table.
DROP TABLE #work_to_do;
GO
Espero ter ajudado!
Pedro Antonio Galvão Junior [MVP | MCC | MSTC | MIE | Microsoft Evangelist | Microsoft Partner | Engenheiro de Softwares | Especialista em Banco de Dados Relacional e Data Warehouse | Professor Universitário | @JuniorGalvaoMVP | http://pedrogalvaojunior.wordpress.com]
Mesmo servidor, mesma query, dois planos de execução diferentes
