What is the maximum number of partition scheme objects, and partition function objects? (SQL Server 2019)
Note, this is not the partition number per table (which is 15 000), but just how much such schema objects can be created?
I'll have a database where each client has a schema, and need to create a dedicated partition scheme and function for each, but cannot find that limit on BOL.
I'll have a database where each client has a schema,
There's your problem. In SQL Server a database is a pretty lightweight container; give each client a database your life will be much easier.
Related
My current database is SQL Server 2008 and will be upgrading to SQL Server 2014. I cannot confirm if SQL Server 2014 supports hash partitions. I have a single table that has about 29M records. This table is growing extremely fast. In the past year it is doubling every 3-4 months. I'd like to horizontally partition my table based on a client id. I've search online and cannot confirm they support it.
No, SQL Server does not support hash partitioning. As Ben says, you can roll your own using a hashing function and a persisted computed column. The only scenario when this is recommended is when latch contention on the last page is slowing down inserts, and no other time. Read Hash Partitioning, SQL Server, and Scaling Writes for more details.
This table is growing extremely fast. In the past year it is doubling every 3-4 months.
So, what does this have to do with hash partitioning, or with any partitioning? Partitioning gives no performance benefits, it purpose is data storage management. For performant access to large datasets, consider indexes. For analytic workloads, use columnstores. For general performance issues read How to analyse SQL Server performance.
Kendra Little has a decent article How To Decide if You Should Use Table Partitioning.
Not directly, but you can "fake it". Specifically, if you come up with your own hashing function (say ClientID modulo «desired number of partitions»), you can use that as your partitioning key (or part of it).
What is the difference between partition and page in SQL Server? Is these are available by default or we need to create explicitly?
Page is the most basic element of storage in SQL Server.
In SQL Server, the page size is 8 KB. This means SQL Server databases
have 128 pages per megabyte. Each page begins with a 96-byte header
that is used to store system information about the page. This
information includes the page number, page type, the amount of free
space on the page, and the allocation unit ID of the object that owns
the page.
Partition:- Partitioning allows a table, index, or index-organized table to be subdivided into smaller pieces, where each piece of such a database object is called a partition. Each partition has its own name, and may optionally have its own storage characteristics. The data of partitioned tables and indexes is divided into units that can be spread across more than one filegroup in a database. The data is partitioned horizontally, so that groups of rows are mapped into individual partitions.
SQL Server 2012 supports up to 15,000 partitions by default. In
earlier versions, the number of partitions was limited to 1,000 by
default. On x86-based systems, creating a table or index with more
than 1000 partitions is possible, but is not supported.
For example, a website offers the ability to create mobile surveys. Each survey ID is a FK in the survey response table, which contains ALL of the survey responses.
What is the size limitation of this table in a SQL Server 2008 db, if the table contains, say 20 varchar(255) fields including the bigint PK & FK?
I realize this would depend on the file size limitation as well, but I would like some more of an educated answer rather than my guess on this.
In terms of searchability, some fields that contain geo-related details such as the survey ID, city, state, and two commends fields would have to be searchable, and thus indexed ... index only these fields?
Also, aged responses would expire after a given amount of time - thus deleted from the table. Does the table, at this point being very large, need to be re-indexed/cleaned up, after the deletions (which would be an automated process)?
Thanks.
Maximum Capacity Specifications for SQL Server
Bytes per row: 8,060
Rows per table: Limited by available storage
Note
SQL Server supports row-overflow storage which enables variable length
columns to be pushed off-row. Only a 24-byte root is stored in the
main record for variable length columns pushed out of row; because of
this, the effective row limit is higher than in previous releases of
SQL Server. For more information, see the "Row-Overflow Data Exceeding
8 KB" topic in SQL Server Books Online
You mention 'table size' -- does this mean number of rows?
Maximum Capacity Specifications for SQL Server
Rows per table : Limited by available storage
As per this Reference, the max size of a table is limited by the available storage.
It sounds like you are going to have a high traffic and high content table. You should consider performance and storage enhancements like Table Partitioning. Also, because this table will be the victim of often INSERTS/UPDATES/DELETES, carefully plan out your indexing, as indexes add overhead for DML statements on the table.
Background
I have a massive db for a SharePoint site collection. It is 130GB and growing at 10gb per month. 100GB of the 130GB is in one site collection. 30GB is the version table. There is only one site collection - this is by design.
Question
Am I able to partition a database (SharePoint) using SQL 2005s data partitioning features (creating multiple data files)?
Is it possible to partition a database that is already created?
Has anyone partitioned a SharePoint DB? Will I encounter any issues?
You would have to create a partition set and rebuild the table on that partition set. SQL2005 can only partition on a single column, so you would have to have a column in the DB that
Behaves fairly predictably so you don't get a large skew in the amount of data in each partition
IIRC the column has to be a numeric or datetime value
In practice it's easiest if it's monotonically increasing - you can create a series of partitions (automatically or manually) and the system will fill them up as it gets to the range definitions.
A date (perhaps the date the document was entered) would be ideal. However, you may or may not have a useful column on the large table. M.S. tech support would be the best source of advice for this.
The partitioning should be transparent to the application (again, you need a column with appropriate behaviour to use as a partition key).
Unless you are lucky enough to have a partition key column that is also used as a search predicate in the most common queries you may not get much query performance benefit from the partitioning. An example of a column that works well is a date column on a data warehouse. However, your Sharepoint application may not make extensive use of this sort fo query.
Mauro,
Is there no way you can segment the data on a Sharepoint level?
ie you may have multiple "sites" using a single (SQL) content database.
You could migrate site data to a new content database, which will allow you to reduce the data in that large content site and then shrink the datafiles.
it will also assist you in managing your obvious continued growth.
James.
I'm comparing between two techniques to create partitioned tables in SQL 2005.
Use partitioned views with a standard version of SQL 2005 (described here)
Use the built in partition in the Enterprise edition of SQL 2005 (described here)
Given that the enterprise edition is much more expensive, I would like to know what are the main benefits of the newer enterprise built-in implementation. Is it just an time saver for the implementation itself. Or will I gain real performance on large DBs?
I know i can adjust the constraints in the first option to keep a sliding window into the partitions. Can I do it with the built in version?
searchdotnet rulz! check this out:
http://www.eggheadcafe.com/forumarchives/SQLServerdatawarehouse/Dec2005/post25052042.asp
Updated: that link is dead. So here's a better one
http://msdn.microsoft.com/en-us/library/ms345146(SQL.90).aspx#sql2k5parti_topic6
From above:
Some of the performance and manageability benefits (of partioned tables) are
Simplify the design and
implementation of large tables that
need to be partitioned for
performance or manageability
purposes.
Load data into a new partition of an
existing partitioned table with
minimal disruption in data access in
the remaining partitions.
Load data into a new partition of an
existing partitioned table with
performance equal to loading the same
data into a new, empty table.
Archive and/or remove a portion of a
partitioned table while minimally
impacting access to the remainder of
the table.
Allow partitions to be maintained by switching partitions in and out of the partitioned table.
Allow better scaling and parallelism for extremely large operations over multiple related tables.
Improve performance over all partitions.
Improve query optimization time because each partition does not need to be optimized separately.
When using the partitioned tables you can more easily move data from partition to partition. You can also partition the indexes as well.
You can also move data from one partition to another table as needed with a single ALTER TABLE command.