I'm trying to first drop the index and then the PK (because ultimately I'm gonna need to do a truncate on this table).
Here's a screen shot of this table and constraints:
Here are the 2 constraints (code obtained from clipboard after I right-click them and do a create to clipboard in SQL 2008):
(the Primary Key)
ALTER TABLE [dbo].[Entry] ADD CONSTRAINT [PK_Entry_Id] PRIMARY KEY CLUSTERED
(
[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
(supposedly this is the create index code, after I do a right-click create to clipboard..but it's the same exact code! not sure why):
ALTER TABLE [dbo].[Entry] ADD CONSTRAINT [PK_Entry_Id] PRIMARY KEY CLUSTERED
(
[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
GO
Dropping the primary key should drop the index as well as the index was automatically created when you created the primary key.
You only need to drop the Foreign Key constraints when you need to truncate a table. This is to make sure there are no tables dependent on it.
You don't need to, and can't, drop the index associated with the primary key. All you need to do is drop the primary key and the index will be removed.
If you're going to truncate the data, you shouldn't have to drop the primary key though.
If you can't truncate the table, then you should remove foreign keys that reference this table. I assume that you removed foreign keys where this table references other tables, because we don't see any in your data.
Constant and index are not the same.
But in some syntax an index is referred to as a constraint.
You have 5 constraints and one index.
You did not like notice it has the same name in both spots PK_Entry_ID.
A PK is an index.
And an index does not prevent a truncate.
A FK prevents a truncate.
If you are tying to drop the index the why are you creating a script to create.
Create a script to drop and drop it.
Related
I created a Role to which this user belongs to, and have set execute rights on multiple Schemas, however on Data Schema i need to be able to dynamically create and delete tables. Based on the screenshot, i gave all available permissions to the role (and user effectively) but when i try creating an index this is the error i get :
Could not create constraint or index. See previous errors
There are no previous errors :(
This is the code that should create the table and indexes :
CREATE TABLE [Data].[24C6B124-137C-4F06-B690-F80C0C0A1347]
(
[ApplicationId] [INT] NOT NULL,
[UUID] [UNIQUEIDENTIFIER] ROWGUIDCOL NOT NULL,
CONSTRAINT [PK_24C6B124-137C-4F06-B690-F80C0C0A1347]
PRIMARY KEY CLUSTERED ([ApplicationId] ASC)
WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF,
IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY];
ALTER TABLE [Data].[24C6B124-137C-4F06-B690-F80C0C0A1347]
ADD CONSTRAINT [DF_24C6B124-137C-4F06-B690-F80C0C0A1347_UUID]
DEFAULT (NEWID()) FOR [UUID];
ALTER TABLE [Data].[24C6B124-137C-4F06-B690-F80C0C0A1347] WITH CHECK
ADD CONSTRAINT [FK_24C6B124-137C-4F06-B690-F80C0C0A1347_Application]
FOREIGN KEY([ApplicationId]) REFERENCES [dbo].[Application] ([ApplicationId])
ON DELETE CASCADE;
rolling back...
If I execute same query with sa level user, it runs with no issues.
My best bet is that this is a permission problem related to some permission required to create indexes, but my search and experiments lead me nowhere.
As i posted a question, i figured it out so let me share :
I needed to add reference permission also on the table [dbo].[Application] that's in dbo Schema unlike table in question that's in Data Schema.
this is my first foray into SSMS/T-SQL (coming from Access). I have a trigger setup that keeps the value of a column in a parent table always equal to the MAX value of a column a child table based on the key between them. To calculate the MAX I have a UDF defined that i Think works ok.
The problem I seem to have is that the trigger executes for EVERY key in the table and not just the one that got updated/deleted/inserted (or so is what I can glean from the debugger).
Here is the parent table:
CREATE TABLE [dbo].[factMeasures](
[MeasureID] [int] IDENTITY(1,1) NOT NULL,
[QARTOD] [int] NULL,
[Param] [char](10) NOT NULL,
[Value] [real] NOT NULL,
CONSTRAINT [PK_factMeasures] PRIMARY KEY CLUSTERED
(
[MeasureID] 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
Here is the child table:
CREATE TABLE [dbo].[dt_QCflags](
[QC_ID] [int] IDENTITY(1,1) NOT NULL,
[fkMeasureID] [int] NOT NULL,
[RuleValue] [int] NOT NULL,
CONSTRAINT [PK_dt_QCflags] PRIMARY KEY CLUSTERED
(
[QC_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
ALTER TABLE [dbo].[dt_QCflags] WITH CHECK ADD CONSTRAINT [FK_dt_QCflags_factMeasures] FOREIGN KEY([fkMeasureID])
REFERENCES [dbo].[factMeasures] ([MeasureID])
ON DELETE CASCADE
GO
ALTER TABLE [dbo].[dt_QCflags] CHECK CONSTRAINT [FK_dt_QCflags_factMeasures]
GO
HEre is the UDF that calculates the MAX value of [RuleValue] for the input [MeasureID]
CREATE FUNCTION [dbo].[MaxQC](#MeasureID INT)
RETURNS INT
AS
BEGIN
RETURN
(SELECT
Max([dt_QCflags].[RuleValue]) AS Max_RuleValue
FROM
dbo.dt_QCflags
WHERE
dt_QCflags.fkMeasureID = #MeasureID
GROUP BY
fkMeasureID);
END
And here is the trigger on the child table:
ALTER TRIGGER [dbo].[UpdateQARTOD]
ON [dbo].[dt_QCflags]
AFTER INSERT, UPDATE, DELETE
AS
BEGIN
UPDATE factMeasures
SET QARTOD = dbo.MaxQC(MeasureID) -- by QARTOD Definition, QARTOD flag is set to the MAX of all sub-test results
END
So what I want is for the column in the parent (factMeasures.QARTOD) to always contain the Maximum of the column in the child table (dt_QCFlags.RuleValue), for the given MeasureID value
When I debug this, it seems to be running the trigger for EVERY record in the parent table, so I think I need to modify the trigger, but i"m not sure how to get the MeasureID of JUST the record that was added/deleted/modified.
I'm guessing it has something to do with the "magic tables" inserted, deleted, etc. but I can't seem to get the syntax right.
Thanks!
I would argue that unless you have a very good reason, storing values that can easily be computed on a query level is a mistake.
This seems like one of many cases I've seen where people think they gain something by storing values on one table that's calculated from values of another table, but in fact the opposite is true - now you have two points of data that needs to be synchronized at all times, and since the process synchronizing them is a trigger, you don't really have control over that - it's quite easy to disable / enable triggers, for instance.
Therefore, My advice to you would be to remove that trigger all together and simply calculate the value when you need to.
Please note that since SQL Server supports max() over(partition by) meaning you don't even need a group by if you want to calculate the max of a column.
Updated Following your comments to the answer, it seems like you have a good reason to store these values.
Having said all that, here's a direct answer to the question you've asked.
In SQL Server triggers, the database enables you to query two special tables called inserted and deleted. These tables contains the data that was (or going to be, in case of instead of triggers) inserted or deleted to the table on which the trigger is declared.
Please note that in SQL Server, triggers are fired per statement, not per row. This means that the inserted and deleted tables might contain 0, 1 or many rows.
If you still want to calculate the value using triggers, I would advise a trigger for insert/update and another trigger for deletes.
This would make for much simpler code.
In the delete trigger, you left join to the deleted table:
UPDATE T
SET QARTOD = MaxValue
FROM factMeasures As T
JOIN
(
SELECT d.fkMeasureID, Max(t.RuleValue) As MaxValue
FROM Deleted AS d
LEFT JOIN dt_QCflags As t
ON d.QC_ID = t.QC_ID
GROUP BY d.fkMeasureID
) as D
ON T.MeasureID = D.fkMeasureID
In the insert/update trigger, you write a very similar code - but you don't need to refer to the physical table in this case, only the inserted table:
UPDATE T
SET QARTOD = MaxValue
FROM factMeasures As T
JOIN
(
SELECT fkMeasureID, Max(RuleValue) As MaxValue
FROM Inserted
GROUP BY fkMeasureID
) as I
ON t.MeasureID = I.fkMeasureID
Working to create an EF6.0 connected DB with MVC5 in VSS2013. Previously the model worked, having been created with EF5.0, MVC3 and VSS2010.
Changes were made to the database on existing tables using MS SQL Express - adding some foreign integer keys on child tables pointing to a master parent record, and a single hand-entered test data record set was created for testing. Some extra properties were added. A couple of new unrelated tables.
The "Update Model From Database" picked up the table changes, but has refused to pick up these FK associations. ALL navigation was missing.
The model was deleted, recreated in EF6.0. Once again the EDMX file picks up all tables, and older FK associations. New ones are simply ignored.
There is no point adding tables here as examples, this is simple Parent Child FK stuff using ints. Scripted SQL shows FK constraints for old and new ones are comparable. I have dropped the model and recreated several times, with different ConnectionStrings, name changing in case of confusion. No joy.
I am totally confused as to why it can pick up some, but not others. I need some "gotcha" clues. Anyone?
EF6.0.0 MVC5.1 .NET4.5
Update: Non-Functional FK example
ALTER TABLE [dbo].[Cli_Address]
ADD CONSTRAINT [FK_Cli_Address_WebUserProfileX] FOREIGN KEY ([UserProfileFK]) REFERENCES [dbo].[WebUserProfile] ([UserID]);
You are hit by this:
http://social.msdn.microsoft.com/Forums/en-US/0ba27be1-d252-44c0-8e0b-7f129b578a2b/missing-navigation-properties-on-entity?forum=adodotnetentityframework
Caused by this unneeded index:
CREATE UNIQUE NONCLUSTERED INDEX [IX_WebProfile] ON [dbo].[WebUserProfile]
(
[UserID] 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
Dropping the index, and everything Works
(I think you will have to drop and recreate the fks before you can drop the index)
UPDATE: I have fixed this, so this scenario is no longer broken , see https://entityframework.codeplex.com/workitem/667
I'm interested in databases and have started to play around with SQL Server 2008, I've read that using appropriate Indexes on tables can help to improve the overall performance of the database.
I have two tables and auto generated 1 million rows in each table using SQL Data Generator, Table 1 is a customers table and Table 2 is a renters table, the designs are as follows:
Customer Renters
CustomerID (PK) RentersID (PK)
ForeName (Non clustered index) StartDate
SurName EndDate
Email RentalNights
CustomerID (FK) (Non Clustered index)
I've read that placing a non clustered index on the most commonly used columns as well as foreign key columns will help to improve performance. I created a simple join query before using indexes and after using indexes, but for me I can't seen the increased performance when using indexes, can any body help me out? The images below are the execution plans before indexes and after using them.
Before Indexes:
After Indexes:
EDIT:
this is the SQL syntax i am using
SELECT cu.ForeName + ' ' + cu.SurName AS 'Name'
FROM dbo.Customers cu
INNER JOIN dbo.Renters re ON re.CustomerID = cu.CustomerID
WHERE cu.ForeName = 'Daniel'
EDIT
This is my index syntax using the ones posted in the reply below:
CREATE NONCLUSTERED INDEX [ix_Customer] ON [dbo].[Customers]
(
[ForeName] ASC,
[CustomerID] ASC
)
INCLUDE ( [SurName]) 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
Based on your query the best nonclustered indexes to build would be:
CREATE NONCLUSTERED INDEX ix_IndexA on dbo.Customers (Forename, CustomerID)
INCLUDE (SurName)
CREATE NONCLUSTERED INDEX ix_IndexB on dbo.Renters (CustomerID)
You want your key fields to be on your filter or JOIN columns, and your INCLUDE columns are at the leaf level to get returned in the SELECT.
Had a super weird issue using Entity Framework (4.x, 5) with SQL Server 2012.
To illustrate I made two tables with very simple 1-to-many relationship
PK. [User].[UserId]
FK. [Order].[UserId]
However EF didn't generate any navigation property for these two tables at all. In the EDMX the two tables are totally separate; no link between them at all.
Then I create the same tables using the same scripts in SQL Server 2008, and all of a sudden everything works as intended as they always have been.
Has anyone had same issues? Is there any solutions for that?
I'm using the SQL Server 2012 Developer Edition from MSDN
CREATE TABLE [dbo].[Users](
[UserId] [int] IDENTITY(1,1) NOT NULL,
[UserName] [varchar](50) NOT NULL,
CONSTRAINT [PK_Users] PRIMARY KEY CLUSTERED
(
[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]
CREATE TABLE [dbo].[Orders](
[OrderId] [int] IDENTITY(1,1) NOT NULL,
[UserId] [int] NOT NULL,
CONSTRAINT [PK_Orders] PRIMARY KEY CLUSTERED
(
[OrderId] 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
ALTER TABLE [dbo].[Orders] WITH CHECK ADD CONSTRAINT [FK_Orders_Users] FOREIGN KEY([UserId])
REFERENCES [dbo].[Users] ([UserId])
GO
ALTER TABLE [dbo].[Orders] CHECK CONSTRAINT [FK_Orders_Users]
GO
You'll need to be more specific about your actual schema and constraint creation scripts, but I can tell you that EF will not map relationships that are created over unique indexes (rather than primary keys). While SQL Server allows for this, EF does not.