作为 SQL SERVER 2012 一大卖点的 CLOUMNSTORE INDEX，先来认识一下。
1，支持数据类型：
int, big int, small int, tiny int, money, smallmoney, bit, float, real, char(n), varchar(n), nchar(n), nvarchar(n), date, datetime, datetime2, small datetime, time, datetimeoffset with precision <=2, decimal or numeric with precision <= 18
2，不支持数据类型：
decimal or numeric with precision > 18, datetimeoffset with precision > 2, binary, varbinary, image, text, ntext, varchar(max), nvarchar(max), cursor, hierarchyid, timestamp, uniqueidentifier, sqlvariant, xml. www.2cto.com
3，不可以用于：
INSERT, UPDATE, DELETE, MERGE
需要
[sql]
ALTER INDEX mycolumnstoreindex ON mytable DISABLE;
ALTER INDEX mycolumnstoreindex ON mytable REBUILD;
4，增加内存：
[sql]
ALTER WORKLOAD GROUP [DEFAULT] WITH (REQUEST_MAX_MEMORY_GRANT_PERCENT=X)
ALTER RESOURCE GOVERNOR RECONFIGURE
GO
--where X is the percent, say 50.
5，查询索引大小：
[sql]
-- total size
with total_segment_size as (
SELECT
SUM (css.on_disk_size)/1024/1024 AS segment_size_mb
FROM sys.partitions AS p
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JOIN sys.column_store_segments AS css
ON p.hobt_id = css.hobt_id
)
,
total_dictionary_size as (
SELECT SUM (csd.on_disk_size)/1024/1024 AS dictionary_size_mb
FROM sys.partitions AS p
JOIN sys.column_store_dictionaries AS csd
ON p.hobt_id = csd.hobt_id
)
select
segment_size_mb,
dictionary_size_mb,
segment_size_mb + isnull(dictionary_size_mb, 0) as total_size_mb
from total_segment_size
left outer join total_dictionary_size
on 1 = 1
go
-- size per index
with segment_size_by_index AS (
SELECT
p.object_id as table_id,
p.index_id as index_id,
SUM (css.on_disk_size)/1024/1024 AS segment_size_mb
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FROM sys.partitions AS p
JOIN sys.column_store_segments AS css
ON p.hobt_id = css.hobt_id
group by p.object_id, p.index_id
) ,
dictionary_size_by_index AS (
SELECT
p.object_id as table_id,
p.index_id as index_id,
SUM (csd.on_disk_size)/1024/1024 AS dictionary_size_mb
FROM sys.partitions AS p
JOIN sys.column_store_dictionaries AS csd
ON p.hobt_id = csd.hobt_id
group by p.object_id, p.index_id
)
select
object_name(s.table_id) table_name,
i.name as index_name,
s.segment_size_mb,
d.dictionary_size_mb,
s.segment_size_mb + isnull(d.dictionary_size_mb, 0) as total_size_mb
from segment_size_by_index s
JOIN sys.indexes AS i
ON i.object_id = s.table_id
and i.index_id = s.index_id
left outer join dictionary_size_by_index d
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on s.table_id = s.table_id
and s.index_id = d.index_id
order by total_size_mb desc
go
-- size per table
with segment_size_by_table AS (
SELECT
p.object_id as table_id,
SUM (cs