Is there any difference between the below 2 CREATE TABLE statements in SQL Server 200x/2012? I generated this script from two different tables, one had a Key name defined (PK_Table1) whereas the other had some kind of randomly generated number associated to it (PK_Table1_1084F446).
CREATE TABLE [dbo].[Table1](
[ID] [uniqueidentifier] NOT NULL,
<<Other Column declaration here>>
PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
Few more non-clustered indexes declaration here
CREATE TABLE [dbo].[Table1](
[ID] [uniqueidentifier] NOT NULL,
<<Other Column declaration here>>
CONSTRAINT [PK_Table1] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
Few more non-clustered indexes declaration here
It works in the same way, but natural names are more convenient:
1) when altering constraint you can easy refer to it (if you gave sensible name);
2) when query failed due to constraint, name of this constraint is showed, so you can easily know what cause an error (if you gave sensible name).
Related
I have table like below:
CREATE TABLE [dbo].[PartitionExample]
(
[dateTimeColumn1] [datetime] NOT NULL,
CONSTRAINT [PK_PartitionExample] PRIMARY KEY CLUSTERED
(
[dateTimeColumn1] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY =
OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
I have created Partition Function like below:
CREATE PARTITION FUNCTION DateRangePF (INT)
AS RANGE RIGHT FOR VALUES ( 20180601,20180901,20181201,20190301)
Then, I have created Partition Scheme for it:
CREATE PARTITION SCHEME DateRangePS
AS PARTITION DateRangePF TO
(FG032018_SampleDB,FG062018_SampleDB,FG092018_SampleDB,
FG122018_SampleDB,FG032019_SampleDB);
Now, When I am applying the partition scheme to this table, I want to apply explicit conversion of [dateTimeColumn1] column of datetime data type to INT Data Type. But when I tried it, I got syntax error:
ALTER TABLE [dbo].[PartitionExample] ADD
CONSTRAINT [PK_PartitionExample] PRIMARY KEY CLUSTERED
(
dateTimeColumn1 ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, ALLOW_ROW_LOCKS =
ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 90)
ON DateRangePS(
convert(INT, CONVERT(CHAR(8), dateTimeColumn1, 112));
Can you guys please let me know
how explicit conversion can be implemented in such scenarios.
Also would it perform better when I will perform explicit conversion of datetime column or char(8) column to INT Column for partition.
Thank you for your help.
I have a reporting requirement from the following tables. I created a new database with these tables and imported data from the live database for reporting purpose.
The report parameter is a date range. I read the following and found that DATE_CORRELATION_OPTIMIZATION can be used to make the query work faster by utilizing seek instead of scan. I made the required settings – still the query is using same old plan and same execution time. What additional changes need to be made to make the query utilize the date correlation?
Note: I am using SQL Server 2005
REFERENCES
Optimizing Queries That Access Correlated datetime Columns
The Query Optimizer: Date Correlation Optimisation
SQL
--Database change made for date correlation
ALTER DATABASE BISourcingTest
SET DATE_CORRELATION_OPTIMIZATION ON;
GO
--Settings made
SET ANSI_NULLS ON
SET ANSI_PADDING ON
SET ANSI_WARNINGS ON
SET ARITHABORT ON
SET CONCAT_NULL_YIELDS_NULL ON
SET QUOTED_IDENTIFIER ON
SET NUMERIC_ROUNDABORT OFF
GO
--Test Setting
IF ( (sessionproperty('ANSI_NULLS') = 1) AND
(sessionproperty('ANSI_PADDING') = 1) AND
(sessionproperty('ANSI_WARNINGS') = 1) AND
(sessionproperty('ARITHABORT') = 1) AND
(sessionproperty('CONCAT_NULL_YIELDS_NULL') = 1) AND
(sessionproperty('QUOTED_IDENTIFIER') = 1) AND
(sessionproperty('NUMERIC_ROUNDABORT') = 0)
)
PRINT 'Everything is set'
ELSE
PRINT 'Different Setting'
--Query
SELECT C.ContainerID, C.CreatedOnDate,OLIC.OrderID
FROM ContainersTest C
INNER JOIN OrderLineItemContainers OLIC
ON OLIC.ContainerID = C.ContainerID
WHERE C.CreatedOnDate > '1/1/2015'
AND C.CreatedOnDate < '2/01/2015'
TABLES
CREATE TABLE [dbo].[ContainersTest](
[ContainerID] [varchar](20) NOT NULL,
[Weight] [decimal](9, 2) NOT NULL DEFAULT ((0)),
[CreatedOnDate] [datetime] NOT NULL DEFAULT (getdate()),
CONSTRAINT [XPKContainersTest] PRIMARY KEY CLUSTERED
(
[CreatedOnDate] ASC,
[ContainerID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
CREATE TABLE [dbo].[OrderLineItemContainers](
[OrderID] [int] NOT NULL,
[LineItemID] [int] NOT NULL,
[ContainerID] [varchar](20) NOT NULL,
[CreatedOnDate] [datetime] NOT NULL DEFAULT (getdate()),
CONSTRAINT [PK_POLineItemContainers] PRIMARY KEY CLUSTERED
(
[OrderID] ASC,
[LineItemID] ASC,
[ContainerID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [IX_OrderLineItemContainers] UNIQUE NONCLUSTERED
(
[ContainerID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
SET ANSI_PADDING OFF
GO
ALTER TABLE [dbo].[OrderLineItemContainers] WITH CHECK ADD CONSTRAINT [FK_POLineItemContainers_Containers] FOREIGN KEY([ContainerID])
REFERENCES [dbo].[Containers] ([ContainerID])
GO
ALTER TABLE [dbo].[OrderLineItemContainers] CHECK CONSTRAINT [FK_POLineItemContainers_Containers]
Plan
--
According to the docs:
https://technet.microsoft.com/en-us/library/ms177416(v=sql.105).aspx
If any one of the datetime columns for which correlation statistics are maintained is not the first or only key of a clustered index, consider creating a clustered index on it. Doing this generally leads to better performance on the types of queries covered by correlation statistics. If a clustered index already exists on the primary key columns, you can modify a table so that the clustered index and primary key use different column sets.
Since your OrderLineItemContainers table has no suitable index by which to filter on the Date, it really can't do anything. Try adding a nonclustered index on the OrderLineItemContainers.CreatedOnDate to see if it will then switch the plan.
It would be better to have it be clustered, but there are other considerations... note you could make the primary key nonclustered, and use the clustered for this new date index if this is the dominant query and this makes it worth it.
So this is optimal:
CREATE TABLE [dbo].[OrderLineItemContainers](
[OrderID] [int] NOT NULL,
[LineItemID] [int] NOT NULL,
[ContainerID] [varchar](20) NOT NULL,
[CreatedOnDate] [datetime] NOT NULL DEFAULT (getdate()),
CONSTRAINT [PK_POLineItemContainers] PRIMARY KEY NONCLUSTERED -- NONCLUSTERED PRIMARY KEY!!
(
[OrderID] ASC,
[LineItemID] ASC,
[ContainerID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [IX_OrderLineItemContainers] UNIQUE NONCLUSTERED
(
[ContainerID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
CREATE CLUSTERED INDEX ON OrderLineItemContainers(CreatedOnDate)
OR you could just try a new NONCLUSTERED index:
CREATE NONCLUSTERED INDEX ON OrderLineItemContainers(CreatedOnDate)
I am designing a database using SQLExpress.
I have a table which has three columns. The table looks as below.
CREATE TABLE [dbo].[dummy](
[id] [int] IDENTITY(1,1) NOT NULL,
[someLongString] [text] NOT NULL,
[someLongText_Hash] [binary](20) NOT NULL,
CONSTRAINT [PK_dummy] PRIMARY KEY CLUSTERED
(
[id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
I already have some data in this table. Whenever I want to add a new row, I first compute a hash on someLongString and query the table to see if a row with this hash already exists. As the table size grows, this query talks longer time and hence I plan to index it by the someLongText_Hash column.
Can some please suggest how to do this in SQL Server Management Studio. Also, after adding this index, how do I index the existing rows in this table ?
Why can't you just set the 'someLongString' field to be unique? That way you don't need to keep a hash and an extra primary key?
You could try using a CHECKSUM.
CREATE TABLE [dbo].[dummy](
[id] [int] IDENTITY(1,1) NOT NULL,
[someLongString] [text] NOT NULL,
[someLongText_CheckSum] NOT NULL,
CONSTRAINT [UC_someLongText_CheckSum] UNIQUE (someLongText_CheckSum),
CONSTRAINT [PK_dummy] PRIMARY KEY CLUSTERED
(
[id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
See here for further explanation
We have an aspnet_Users table from aspnet membership table that shows up with
almost 18 gb index size.
rows 251172
datasize 56472 KB
indexsize 17800536 KB
This is just the standard aspnet membership table, but we do have an other table with a foreign key to this table (userid column).
Anyone seen this problem before?
How can i reduce the index size?
the aspnet_Users table is defined as
CREATE TABLE [dbo].[aspnet_Users](
[ApplicationId] [uniqueidentifier] NOT NULL,
[UserId] [uniqueidentifier] NOT NULL,
[UserName] [nvarchar](256) NOT NULL,
[LoweredUserName] [nvarchar](256) NOT NULL,
[MobileAlias] [nvarchar](16) NULL,
[IsAnonymous] [bit] NOT NULL,
[LastActivityDate] [datetime] NOT NULL,
PRIMARY KEY NONCLUSTERED
(
[UserId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
CREATE UNIQUE CLUSTERED INDEX [aspnet_Users_Index] ON [dbo].[aspnet_Users]
(
[ApplicationId] ASC,
[LoweredUserName] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
CREATE NONCLUSTERED INDEX [aspnet_Users_Index2] ON [dbo].[aspnet_Users]
(
[ApplicationId] ASC,
[LastActivityDate] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
ALTER TABLE [dbo].[aspnet_Users] ADD DEFAULT (newid()) FOR [UserId]
GO
ALTER TABLE [dbo].[aspnet_Users] ADD DEFAULT (NULL) FOR [MobileAlias]
GO
ALTER TABLE [dbo].[aspnet_Users] ADD DEFAULT ((0)) FOR [IsAnonymous]
GO
ALTER TABLE [dbo].[aspnet_Users] WITH NOCHECK ADD FOREIGN KEY([ApplicationId])
REFERENCES [dbo].[aspnet_Applications] ([ApplicationId])
GO
This works out at 70k per row though which is more then a single extent (8 pages, 64k) which implies massive fragmentation.
Have you ever run index maintenance on it? Run this and see what happens
ALTER INDEX ALL ON aspnet_Users REBUILD
Alternatively, has the table ever been extended with a LOB (pictures, XML etc) column? Or has someone added dozens of indexes? So please add the actual in-use table definition
Edit: remove the index on LastActivityDate, or change it to smalldatetime to keep minute accuracy, or only update it if changed more then xx seconds/minutes
Hey everyone, I'm trying to create a database for a personal friend of mine and given my inexperience with developing databases I'm having difficulty trying to establish one I'm currently dealing with. Essentially, my is issue is with my "rooms" table which has an association with another table called "location"; The location is the is everything you would expect (buildingID, streetAddress,etc.), and Room has a foreign key containing the buildingId. I want my "rooms" table to have unique values for room numbers based on the buildingId.
To give you a clearer idea, I'll just c&p the script I'm using to create those tables.
CREATE TABLE [dbo].[Location](
[buildingId] [int] IDENTITY(1,1) NOT NULL,
[streetAddress] [varchar](50) NOT NULL,
[postalCode] [varchar](7) NOT NULL,
[province] [varchar](30) NOT NULL,
[city] [varchar](30) NOT NULL,
CONSTRAINT [PK_Location] PRIMARY KEY CLUSTERED
(
[buildingId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [UN_postalCode] UNIQUE NONCLUSTERED
(
[postalCode] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [UN_streetAddress] UNIQUE NONCLUSTERED
(
[streetAddress] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
CREATE TABLE [dbo].[Room](
[rmId] [int] IDENTITY(1,1) NOT NULL,
[roomNum] [varchar](10) NOT NULL,
[floor] [int] NOT NULL,
[capacity] [int] NOT NULL,
[permission] [bit] NOT NULL,
[buildingId] [int] NOT NULL,
CONSTRAINT [PK_Room_1] PRIMARY KEY CLUSTERED
(
[rmId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
SET ANSI_PADDING OFF
GO
ALTER TABLE [dbo].[Room] WITH CHECK ADD CONSTRAINT [FK_Room_Location] FOREIGN KEY([buildingId])
REFERENCES [dbo].[Location] ([buildingId])
GO
ALTER TABLE [dbo].[Room] CHECK CONSTRAINT [FK_Room_Location]
GO
Any help would greatly be appreciated.
Thanks.
A table level unique constraint?
ALTER TABLE dbo.Room WITH CHECK ADD
CONSTRAINT UQ_Room_RoomBuildingLocation UNIQUE (roomNum, buildingId)
This can be a unique index too which would allow INCLUDE columns