Just a SQL Server 2008 generic question, I have a table that has around 15 columns and they are string, int and bool types only, I am not storing any binary data, and I have auto generated PK column "ID" with ##IDENTITY enabled to generate unique ID on every entry, my question is that a table like this how many rows can have, is there any row limitation in SQL Server table?
thanks in advance.
There are limits defined in "Maximum Capacity Specifications for SQL Server" on MSDN
Some relevant ones
1024 columns per standard table
Rows per table: Limited by available storage
Bytes per row: 8060 (except for row overflow data)
Basically, don't worry...
Related
We have an SQL Server database tables that are running out of ids soon (the primary id is a 32-bit integer and the max id is already about 2 billion). What is the best way to fix this issue?
Multiple attributes (3) in a table have Sequential ID and the range is expected to get exhausted soon
Alter the id type to 64-bit is an option but that would bring down the database for too long because the table has billion of rows.
are there any information in the net, where i can verify how hight are the storage costs for temporal tables feature?
Will the server creates a the full hardcopy of the row/tuple that was modified?
Or will the server use a reference/links to the original values of the master table that are not modified?
For example. I have a row with 10 columns = storage 100 KB. I change one value of that row, thow times. I have thow rows in the historical table after that changes. Is the fill storage cost for the master und historial table then ~300KB?
Thanks for every hint!
Ragards
Will the server creates a the full hardcopy of the row/tuple that was
modified? Or will the server use a reference/links to the original
values of the master table that are not modified?
Here is the cite of the book Pro SQL Server Internals
by Dmitri Korotkevitch that ansers your question:
In a nutshell, each temporal table consists of two tables — the
current table with the current data, and a history table that stores
old versions of the rows. Every time you modify or delete data in
the current table, SQL Server adds an original version of those rows
to the history table.
A current table should always have a primary key defined. Moreover,
both current and history tables should have two datetime2 columns,
called period columns, that indicate the lifetime of the row. SQL
Server populates these columns automatically based on transaction
start time when the new versions of the rows were created. When a row
has been modified several times in one transaction, SQL Server does
not preserve uncommitted intermediary row versions in the history
table.
SQL Server places the history tables in a default filegroup, creating
non-unique clustered indexes on the two datetime2 columns that
control row lifetime. It does not create any other indexes on the
table.
In both the Enterprise and Developer Editions, history tables use
page compression by default.
So it's not
reference/links to the original values of the master table
Previous row version is just copied as it is into historical table on every mofification.
Why does SQL Server sometimes not provide sequence no in identity columns? For example we were inserting records into the table; until 300 it was ok, but for the next record the id which was assign it 318 - an 18 numbers gap in identity column.
Can anyone tell me why? And I have seen this for other tables as well one number or two number gap between the before and after.
No records deleted
Thanks
I've got data potentially to be pushed to SQL-ce on a 3rd party windows phone application but I don't have anywhere to conduct a test so I need to figure if we'll exceed the 4Gb max database size (many millions of records).
I know the sizes of various data types but are there additional requirements for indexes, row id's, etc. Also this data will need to be synchronized/replicated so I assume every row needs a GUID or the like as well?
Table1 (first 2 fields are clustered primary key)
nvarchar(20)
int
int
datetime
Table2 (First field is primary key)
int
int
datetime
Table3 (First two fields are clustered primary key)
int
int
int
I have access to Sql Server (not CE) but I'm an Oracle guy and don't know my way around there very well. Any help or insight is appreciated.
This will be a starting point: http://support.microsoft.com/kb/827968
I have command line tools to migrate from SQL Server to SQL Compact, that will give you more rprecise results: http://exportsqlce.codeplex.com
Also, Merge replication adds columns and system tables to your database.
Luckily your tables are very narrow, so the 4 GB can be stretched to a ton of rows. Every row will need a GUID, you're correct. Look into SEQUENTIALID, which will keep your records in some sort of order, reducing some performance hindrances of GUIDs. Do you currently have access to the data, or do you have a rough estimate of how many records you'll be storing? If you have the data I'd create a clean DB, create your tables and insert it. Index it to your liking and check the size. Indexes can take up quite a bit of space, but you shouldn't need much in the way of indexes on these narrow tables.
Using SQL Server 2005 and 2008.
I've got a potentially very large table (potentially hundreds of millions of rows) consisting of the following columns:
CREATE TABLE (
date SMALLDATETIME,
id BIGINT,
value FLOAT
)
which is being partitioned on column date in daily partitions. The question then is should the primary key be on date, id or value, id?
I can imagine that SQL Server is smart enough to know that it's already partitioning on date and therefore, if I'm always querying for whole chunks of days, then I can have it second in the primary key. Or I can imagine that SQL Server will need that column to be first in the primary key to get the benefit of partitioning.
Can anyone lend some insight into which way the table should be keyed?
As is the standard practice, the Primary Key should be the candidate key that uniquely identifies a given row.
What you wish to do, is known as Aligned Partitioning, which will ensure that the primary key is also split by your partitioning key and stored with the appropriate table data. This is the default behaviour in SQL Server.
For full details, consult the reference Partitioned Tables and Indexes in SQL Server 2005
There is no specific need for the partition key to be the first field of any index on the partitioned table, as long as it appears within the index it can then be aligned to the partition scheme.
With that in mind, you should apply the normal rules for index field order supporting the most queries / selectivity of the values.