We are on SQL 2014...we have a bunch of views in a database where we are trying to find the views which have more than 16 columns max for unique index/constraint...this is needed so we can convert them to indexed views...
View 1 Repliesi just got an error in my application when i tried to do an insert stating that there was a "unique key constraint".
I have the database open with sql server management studio and i need to find out how to view the constraints?
How do i navigate to see the constraints on a table?
Thanks
Hi,
When I create a unique constraint, SQL Server automatically creates an index on this constraint. So when I run the following...
ALTER TABLE PersonsProjects
WITH NOCHECK ADD CONSTRAINT NoDupes UNIQUE NONCLUSTERED (PersonID, ProjectID)
...SQL Server will create a composite index on PersonsProjects called NoDupes on PersonIDand ProjectID. Thing is, I need this index to include a third column Status since most queries use this column in conjunction with PersonID and ProjectID. If there was no index on this table, I would have created it as follows:
CREATE UNIQUE INDEX NoDupes ON PersonsProjects (PersonID, ProjectID) INCLUDE (Status) WITH IGNORE_DUP_KEY
But this won't enforce the unique constraint on PersonID and ProjectID when performing inserts and updates. Is there any way of creating a unique constraint with an included column?
I would rather not have two indexes...
NoDupes: PersonID,ProjectID
New Index: PersonID,ProjectID INCLUDE Status
...so I'm trying to determine what other options that might be available...please advise.
Thanks much.
A UNIQUE INDEX must inherently impose a unique constraint and a UNIQUE CONSTRAINT is most likely implemented via a UNIQUE INDEX. So what is the difference? When you create in Enterprise Manager you must select one or the other.
View 8 Replies View RelatedHelloWhat should I use for better perfomance sinceunique constraint always use index ?ThanksKamil
View 5 Replies View RelatedWhat's the difference in the effect of the followings:
CREATE UNIQUE NONCLUSTERED INDEX
and
ALTER TABLE dbo.titles ADD CONSTRAINT
titleind UNIQUE NONCLUSTERED
I found there're two settings in Indexs/Keys dialog box of the management studio, Is Unique, and Type. The DDL statements above are generated by setting Is Unique to yes plus Type to Index, and just Type to Unique Key, respectively. What's the difference between them?
I have an issue where I am getting an error on an unique index.
I know why I am getting the error but not sure how to get around it.
The query does a check on whether a unique value exists in the Insert/Select. If I run it one record at a time (SELECT TOP 1...) it works fine and just won't update it if the record exists.
But if I do it in a batch, I get the error. I assume this is because it does the checking on the file before records are written out and then writes out the records one at a time from a temporary table.
It thinks all the records are unique because it compares the records one at a time to the original table (where there would be no duplicates). But it doesn't check the records against each other. Then when it actually writes out the record, the duplicate is there.
How do I do a batch where the Insert/Select would write out the records without the duplicates as it does when I do it one record at a time.
CREATE TABLE #TestTable
(
Name varchar(50),
Email varchar (40)
)
Insert #TestTable (Name,Email) Values('Tom', 'tom@aol.com')
[Code] .....
Hi everyone,
I need urgent help to resolve this issue...
As far as the performance goes which one is better..
Unique Index(col1, col2) OR Unique constraint(col1, col2) ?
Unique constraint automatically adds a unique index
and unique index takes care of uniqueness then whats the use of unique constraint ?
Which one do one use ?
thanks
sonali
BOL says a unique constraint is preferred over a unique index. It also states that a unique constraint creates a unique index. What then is the difference between the two, and why is a constraint preferred over the index?
View 2 Replies View RelatedAny easy way to find if there are any nested views existing in the database?...using SQL server 2014...
View 1 Replies View RelatedI'm trying to weight the pros and cons of unique constraints and unique indexes. I understand that creating a unique constraint also creates an index. If that is the case, why not just use a unique index? Could someone give me an example of when you would want an unique constraint over an unique indexes
Thanks in advance
What is the difference between unqiue constraint and unique index? What are the pros and cons? Are they interchangable?
------------------------
I think, therefore I am - Rene Descartes
When I add a unique key constraint to column in SQL 6.5 why does it alsocreate an index. e.g. In the table subaccounts I added a unique keyconstraint for the column login and SQL creates an index with the nameUQ_SubAccounts_2__19 (UKC).Does this also mean that there is no need to create an index for thiscolumn?thxMansoor
View 2 Replies View RelatedI am creating a new SSIS package where there is a flat file (CSV) I am importing. Well, there will be an end-user using a web UI to initiate the import of the file. However, this flat file is generated from another company and then uploaded to our network.
This flat file has the potential to have duplicate rows that would have already been imported at a previous date. With the constraints in the table, we have guaranteed that there will not be duplicates added, but the SSIS package fails immediately upon attempting to insert a duplicate row - and the bulk update is rolled back.
What I need to be able to do is load all of the rows that are not duplicates into the table. I am guessing that with my current approach, this is not possible. I am using a Data Flow task that converts the data in the flat file and then performs a bulk copy to load the data into the table.
How can I either ignore duplicate rows, or otherwise gracefully handle this data import?
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All,What's the difference between a unique contraint and unique?sementically, if you want a column contain unique values, it is acontraint. And an index is for searching/sort. The questions are:1. Does a unique constraint interally use unique index?2. If Yes to #1, I DO NOT need to create an index for search/sortpurpose, right?3. If Yes to #2, What's better?4. Also for Primary Key column, it is actually a special uniquecontraint. Not need to create index on PK column for searching/sorting,correct?5. Also for FK contraint, no need to create an index forsearching/sorting?ThanksJohn
View 4 Replies View RelatedI want to create a lot of index for my database for performance.
But I need find memory usage by indexes.
How to find memory usage by index in sql server?
Can you create a unique constraint on multiple columns, or does it haveto be implemented as a unique index?If possible can someone please post some sample code?Thanks,
View 4 Replies View RelatedHi Guys.
I have a problem. I have two feilds in a table. Both of them are (int). I want to be able make sure the same number is not put in both columns for each row. Both colums have to be a different number, and also if one is null, the other cannot be. How do I go about enforcing this policy?
For Example:
This is what I want
ID Column1 Column2
--- -------- ---------
1 5 8
2 5 7
3 null 10
4 6 2
This is what I DO NOT want:
ID Column1 Column2
--- -------- ---------
1 5 5
2 5 5
3 7 7
4 null null
I created a unique constraint between the 2 columns, but it still allows dups within the row. Please help me.
I am trying to create a Unique Constraint on a SQL Server 2005 table where the uniqueness is based on 2 columns.
Could anybody provided some help on how I could enforce this on an existing table (link, or example) I have been looking around without luck.
Thanks in advance
John.
I find to be able to have multiple NULL entries in the following constraint:
Code:
CREATE UNIQUE INDEX my_uidx ON my_table(my_col1,my_col2) WHERE ??? IS NOT NULL;
But is not possible to check multiple columns in "WHERE".
I using SQL Server 2012 Express
I have many databses and we are trying to see how many can be replicated. Found out 90 on't have primary keys.
Next option, find unique indexed tables and convert them to PKeys. Now my question is how do I fin that a table has a unique index and column has "allow null" Please remember I am not asking to find Unique constraint.
In other words , folowing query
select TABLE_NAME from INFORMATION_SCHEMA.TABLE_CONSTRAINTS where CONSTRAINT_TYPE in('UNIQUE') won't tell you if a table has a unique index.
Please help.
my table :
CREATE TABLE [dbo].[users] (
[ID] [int] NOT NULL ,
[A1] [nvarchar] (100) NULL ,
[A2] [nvarchar] (100) NULL ,
[A3] [nvarchar] (100) NULL
) ON [PRIMARY]
i must keep ID columns as primary key
ALTER TABLE [dbo].[users] WITH NOCHECK ADD
CONSTRAINT [PK_users] PRIMARY KEY CLUSTERED
(
[ID]
) ON [PRIMARY]
but now A1+A2 must be unique
how can i do it ?
thank you
Hi,I would like to add a unique index that consists of two fields in atable.e.g. tbl_A (field1,field2) -- field1 & field2 Indexed and combinationmust be Unique.Can anyone tell me the actual sql syntax to create this index?Thanks,June.
View 3 Replies View RelatedHello, I will explain myself further. I want to make my table in such a way that no two colums have the same value for example:
Row 1 - Column 1 = "cool"
Row 1 - Column 3 = 91
Row 3 - Column 1 = "cool"
Row 3 - Column 3 = 91
I dont care about one column having duplicate values, I want to protect against Column 1 and 3 having the same values on other rows. Is this possible to do in sql server?
write a query which retrieves only unique rows excluding some columns.
IdStatusmanager Team Comments Proj number Date
19391New XUnassigned One 3732.0 16-Apr-14
19392Can YCustomer Two 3732.0 17-Apr-14
19393Can YCustomer Two 3732.0 17-Apr-14
19394Can YCustomer One 3732.0 18-Apr-14
19395New YCustomer One 3732.0 19-Apr-14
19396New YCustomer One 3732.0 21-Apr-14
19397New ZCustomer One 3732.0 20-Apr-14
In the above table project number and id shouldn't be considered and I should get the unique rows considering rest of columns and sorted based on date. Expected result is
IdStatusmanager Team Comments Proj number Date
19391New XUnassigned One 3732.0 16-Apr-14
19392Can YCustomer Two 3732.0 17-Apr-14
19394Can YCustomer One 3732.0 18-Apr-14
19395New YCustomer One 3732.0 19-Apr-14
19397New ZCustomer One 3732.0 20-Apr-14
19396New YCustomer One 3732.0 21-Apr-14
I am really puzzled by an apparent difference between table index key column order and its statistics order. I was under understanding that index statistics mirror index definition. However, in my db 2470 index ordinal definitions match statistics definition but 66 do not. I also can reproduce such discrepancy in 2008 R2, 2012 and 2014.
As per definition,
stats_column_id
int
1-based ordinal within set of stats columns
This script duplicates this for me.
BEGIN TRAN
GO
use tempdb
GO
CREATE TABLE [dbo].[ItemProperties](
[itmID] [int] NOT NULL,
[cpID] [smallint] NOT NULL,
[ipuID] [tinyint] NOT NULL,
[Code] ....
The result I get is this:
object_id stats_name
stats_column_list
1525580473 PK_ItemProperties_itmID_ipuID_cpID itmID, cpID, ipuID,
and
object_id index_name
index_column_list
1525580473 PK_ItemProperties_itmID_ipuID_cpID itmID, ipuID, cpID,
Also a query I used to discover this in my db is:
WITH stat AS
(
SELECT
s.object_id
,s.name as stats_name
,(
SELECT
c.name + ', ' as [data()]
FROM sys.stats_columns as sc
[Code] .....
This index is not unique
ix_report_history_creative_id
Msg 2601, Level 14, State 1, Procedure DFP_report_load, Line 161
Cannot insert duplicate key row in object 'dbo.DFP_Reports_History' with unique index 'ix_report_history_creative_id'.
The duplicate key value is (40736326382, 1, 2015-07-03, 67618862, 355324).
Msg 3621, Level 0, State 0, Procedure DFP_report_load, Line 161
The statement has been terminated.
Exception in Task: Cannot insert duplicate key row in object 'dbo.DFP_Reports_History' with unique index 'ix_report_history_creative_id'. The duplicate key value is (40736326382, 1, 2015-07-03, 67618862, 355324).
The statement has been terminated.
In SQL 2012.A query that joins 2 table, with order by clause doesn't get sorted and the result set is not ordered. This happens when some of the columns in the where criteria are in a unique index which is the index that is used for the join between the 2 tables, and all the columns in the unique index are in the where criteria.In the query plan there is no component for sort.The work around was to drop the unique index, or change it to a non-unique index. Once this was done, the execution plan was changed to add the sort component (even when the index was changed to non-unique and the join was still using this index).
View 4 Replies View RelatedWhy we the Unique Constraint doesn't allow the multiple null values in Sql Server?
View 2 Replies View RelatedWe are using SQL CE 3.5 on tablet PCs, that synchs with our host SQL 2005 Server using Microsoft Synchronization Services. On the tablets, when inserting a record, we get the following error:
A duplicate value cannot be inserted into a unique index. [ Table name = refRegTitle,Constraint name = PK_refRegTitle
But the only PK on this table is RegTitleID.
The table structure is:
[RegTitleID] [int] IDENTITY(1,1) NOT NULL,
[RegTitleNumber] [int] NOT NULL,
[RegTitleDescription] [varchar](200) NOT NULL,
[FacilityTypeID] [int] NOT NULL,
[Active] [bit] NOT NULL,
The problem occurs when a Title Number is inserted and a record with that number already exists. There is no unique constraint on Title Number.
Has anyone else experienced this?
Here is My requirement, I'm not sure if this is possible. Creating table called master like col1, col2 col3, col4 , col5 ...Where Col1, col2 are updatable - this can be done easily
Col3, col4 are columns in another table but these can be just a read only ?? Is this possible ? this is possible with View but not friendly with share point CRUD...Col 5 is a computed column of col 2 and col5 ? if above step can be done then sure this can be done I guess.
What is unique index in sql server 2k?
plz some one help me out, thanx
Rahul Arora
07 Batch
NCCE Israna,
######################
IMPOSSIBLE = I+M+POSSIBLE
I'm trying to do the following and haven't been able to figure it out.
Say there's a table with these records:
Col1 Col2 Col3
a b c
a b c
a b d
e f g
e f g
I want to generate a number that represents the groups of columns like this:
Col1 Col2 Col3 MyNumber
a b c 1
a b c 1
a b d 2
e f g 3
e f g 3
So that each grouping gets its own identifier. I've tried this:
SELECT Col1, Col2, Col3
row_number() OVER (PARTITION BY Col1, Col2, Col3
ORDER BY Col1, Col2, Col3) AS MyNumber
FROM MyTable
But I get this:
Col1 Col2 Col3 MyNumber
a b c 1
a b c 2
a b d 1
e f g 1
e f g 2