Unique Index Vs Unique Constraints
Mar 26, 2008
hi team,
.Can i create umique constraint with out unique index.when i am creating a unique constraint sql creates a unique index (default) can i have only unique constraint ?
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SQL Server 2012 :: Failing On Update With Unique Index Error (Not Unique)
Jul 5, 2015This 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.
What Is The Difference Between A UNIQUE INDEX And A UNIQUE CONSTRAINT?
Sep 22, 2004A 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 RelatedUnique Constraint Vs Unique Index In MS SQL 2000
Jul 20, 2005HelloWhat should I use for better perfomance sinceunique constraint always use index ?ThanksKamil
View 5 Replies View RelatedUnique Constraint And Unique Index, What's The Difference?
Jun 24, 2006What'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?
Unique Index Vs Unique Constraint
Mar 7, 2001Hi 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
Unique Constraint Vs Unique Index
Jan 20, 2006BOL 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 RelatedWhat 's Difference Between Unique Key And Unique Index
Nov 13, 2007What 's difference between Unique key and unique index in SQL server 2005?
View 9 Replies View RelatedUGH! Failed To Enable Constraints. One Or More Rows Contain Values Violating Non-null, Unique, Or Foreign-key Constraints.
Jan 9, 2007I know this is probably a flick of a switch but I cannot figure out which switch. Setup is SQL Server / Stored Procedures / DAL / BLL(skipped for testing) / PL. The stored procedure queries from only one table and two columns are ignored because they are being phased out. I can run the stored procedure and preview the data in the DAL but when I create a page with an ODS linked to the DAL and a GridView I get this error. I checked every column that does not allow nulls and they all have values. I checked unique columns (ID is the only unique and is Identity=Yes in the table definition). I checked foreign-key columns for values that are not in the foreign table and there are none. Any ideas why do I get this?
Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.
Failed To Enable Constraints. One Or More Rows Contain Values Violating Non-null, Unique, Or Foreign-key Constraints.
Jan 17, 2008Hi,
I am getting the above error when trying to load a report into my Web Application, I have tracked the error down to one specific field in my database. Even though this field is a NVarChar field and is of size 30 it would seem that there is an issue returning the value from the field. I can write it into the database no problems but when I try to get it out of the database it returns the above error.
e.g
MOB 401.908.804 - Fails
0401.907.324 - okay
8239 9082 (pager) - fails
Anyone got an idea on how to fix this????
Regards..
Peter.
Unique Constraints
Dec 13, 2007I need to ensure that each record in a table is unique in terms of two fields. E.g. Job No. 1 and Phase 1 cannot exist twice. I've tried to achieve this using a compound primary key but am having no joy. Im sure its a simple issue, any suggestions?
Thanks
Alex
Check / Unique Constraints
Apr 18, 2001Hello, I want to write a unique constraint that applies to more than one column. What I mean is that the uniqueness should be that if column A is 5 and column B is 3 no other row where A and B has those values can exist.
Do I write this as a check constraint ? Or how do I do it ?
Also, is there anyone who knows some good reading on how to use Link Tables (many to many relations) in MS SQL Server ?
UNIQUE Constraints In Enterprise Manager
Feb 28, 2004Can anybody help me with specifing a UNIQUE Constraint when creating a table in enerprise manager?
View 1 Replies View RelatedDB Design :: Unique And Check Constraints
Sep 3, 2015I have one table like below Test table. My requirement is to create constraints to confirm <g class="gr_ gr_331 gr-alert gr_gramm Grammar only-ins replaceWithoutSep" data-gr-id="331" id="331">uniqueness</g> of STID value 101 with LN.
like
ID - LN - STID
1 - 'ABC' - 101 ---- Valid Row
2 - 'ABC' - 202 --- Valid Row
3 - 'ABC' - 202 --Valid Row (as I want only unique when LN = 'ABC' with STID = 101)
4 - 'ABC' - 101 -- Invalid Row (As I want uniqueness base on LN and STID = 1011)
create table dbo.Test
(
ID int identity,
LN varchar(50),
STID bigint
)
Is this possible with constraints as I don't want to use <g class="gr_ gr_1041 gr-alert gr_gramm Grammar only-ins doubleReplace replaceWithoutSep" data-gr-id="1041" id="1041">trigger</g>.
What Is The Constraints Expression For Unique(Column)?
Oct 8, 2007I am in the "Check Constraints" window trying to add a constraint that during inserts only allow distinct Column2 insertions. What is the Expression for that? I tried UNIQUE(Column2) it give me an error.
Here is my table definition:
Column Name Data Type Allow Nulls
--------------------------------------------------------------------------------------------
Column1(PrimaryKey) int No
Column2 nvarchar(MAX) No
Checking For Unique Constraints During A Batch Update
Jan 28, 2004hello .
i have a grid for a table that gets updated with recordset.updatebatch
for a multi-user application.
the problem is that some of the table fields have to be unique
now imagine the next situation.
user A opens the form
user B opens the form
user A writes '1000' in the unique field
user A saves the recordset with updatebatch
user B writes '1000' in the unique field
user B saves the recordset with updatebatch
now there will be two records with the field '1000' !
how can i avoid this ?
i cannot check for unique during the update event of the grid
because it should check during the time it is saving and not
when it is just entering data without having updated the recordset
thanks !
SQL 2012 :: After Trigger Not Able To Update Multiple Records With Unique Constraints
Jan 15, 2015I have a After insert, update trigger. When I update multiple records with unique constraints column in it update fails. But if this a single record update it works.
Could like to know the reason.
Unique Index
Mar 29, 2004Just found out that creating a unique index does not create a unique constraint, but creating a unique constraint creates unique index.
But effectively they do the same thing.
Unique Index
May 8, 2008How to findout whether a Index is unique or not?
------------------------
I think, therefore I am - Rene Descartes
Unique Index
Mar 26, 2007if this question is inappropriate here, I apologize (it's at least obliquely related). I have been using ssno as a unique key in a datawarehouse I have been working on because all of the component systems have had it. I now have a database to add where ssno is not available. I have first, last address, city, state,zip and dob.
Question is, how to construct a unique identifier from those components. If not unique, then at least usable?
Again, if this post is wrong here, I apologize
Thanks for any input
Walter
Can't Add Bit Column To Unique Index
Feb 6, 2007This is for SQL 2000 (SP 2) using Enterprise Manager. I have a table with a unique index comprised of several int fields. The index needs to include an additional bit field that is part of the table. But when I go to modify the index, the bit field name doesn't appear in the Column Name list.
Can anyone shed any light on the problem?
Thanks.
Better Performance With Unique Index?
May 21, 2002I have read that you get better performance with unique indexes rather than non-unique indexes.
I have experimented with this in SQL 2000. I have two identical tables (with about 250000 rows each) with a 12-character unique column. In one table I define it as a regular index and in the other I define it as a unique index. No matter what I try I get identical performance, and the query optimizer shows an identical plan.
I even tried clauses such as
WHERE 1 < (SELECT COUNT(*) FROM TheTable
WHERE key_column = OtherTable.key_column)
which should obviously return nothing if TheTable.key_column is unique. However the query still ran a long time no matter if the index is unique or not.
I have also tried a unique constraint instead of a unique index and got the same (non)results.
Can anyone come up with an example where creating a unique index actually makes a performance difference?
UNIQUE INDEX If Not NULL
Dec 17, 2006Hello !
for MS SQL 2000
how can i set an unique index on Serial column but only if Serial IS NOT NULL
CREATE UNIQUE INDEX [IX_Product] ON [Product]([Serial]) ON [PRIMARY]
i can have 100 rows with a NULL Serial
thank you
Unique Index On 2 Columns?
Apr 19, 2013I 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
Unique Constraint/index
Feb 12, 2004I'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
Unique Constraint/Index
May 7, 2008What 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
Unique Index In Sql Server
Mar 4, 2008What is unique index in sql server 2k?
plz some one help me out, thanx
Rahul Arora
07 Batch
NCCE Israna,
######################
IMPOSSIBLE = I+M+POSSIBLE
Creating A Unique Index
Jul 20, 2005HiI tried the following from the help file...When you create or modify a unique index, you can set an option toignore duplicate keys. If this option is set and you attempt to createduplicate keys by adding or updating data that affects multiple rows(with the INSERT or UPDATE statement), the row that causes theduplicates is not added or, in the case of an update, discarded.For example, if you try to update "Smith" to "Jones" in a table where"Jones" already exists, you end up with one "Jones" and no "Smith" inthe resulting table. The original "Smith" row is lost because anUPDATE statement is actually a DELETE followed by an INSERT. "Smith"was deleted and the attempt to insert an additional "Jones" failed.The whole transaction cannot be rolled back because the purpose ofthis option is to allow a transaction in spite of the presence ofduplicates.But when I did it the original "Smith" row was not lost.I am doing something wrong or is the help file incorrect.Dan
View 3 Replies View RelatedUnique Constraint Index
Jul 20, 2005When 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 RelatedDouble Unique Index
Aug 21, 2007
Hello.
I have a question. I need to make a double unique index on a table. for example: I have 2 columns, ColumnA and ColumnB. ColumnA can have duplicate values, so is ColumnB, but it should be impossible to have duplicate values on both columns. for example:
Row 1:
ColumnA = 1, ColumnB = 2
Row2:
ColumnA = 1, ColumnB = 2
this shouldn't be possible.
Row1:
ColumnA = 1, ColumnB = 2
Row2:
ColumnA = 1, ColumnB = 3
this should be possible
is there any way I can do this?
thanks in advance
PK Vs Unique Clustered Index
Aug 20, 2007When not using any enforced relationships in a database (which I know we should, but I like most of you, have inherited sub-optimal design), is there any real difference between using a Primary Key (to which no foreign keys are tied) and using a Unique Clustered index?
Thanks for your thoughts
Unique Index, SQL 2005
Jan 30, 2008
Is there a simple way to find properties of an index for a table? Specifically I am looking for the unique property. I currently have code to to do this, however I feel like there must be some easier way.
I am using .net 2005 and SQL 2005 coding in c#. Thanks for any help!
Code Snippet
_conn.Open();
SqlCommand cmd = new SqlCommand("sp_helpindex", _conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add(new SqlParameter("@objname", "TABLENAME"));
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(results);
foreach (DataRow row in results.Tables[0].Rows)
{
ArrayList names = new ArrayList();
DataTable dtUnique = new DataTable();
SqlCommand cmd2 = this._conn.CreateCommand();
cmd2.CommandText = String.Format("SELECT INDEXPROPERTY(OBJECT_ID('TABLENAME'), 'INDEXNAME', 'IsUnique') AS isUnique");
dtUnique.Load(cmd2.ExecuteReader());
bool unique = Convert.ToBoolean(dtUnique.Rows[0]["isUnique"]);
if (unique)
names.Add(tableName);
}
_conn.Close();
How To Create Unique Secondary Index ?? HELP
Apr 3, 2007I have created the companyid as Primary Key.How to create a unique secondary index on Company Name. To avoid inserting duplicate records in database with the same companyname. I m creatin database in sql server 2005 with asp.net C# 2005. I know one way is write the query if not exists at the time of insert.But,i want to know is there anyother way to make a unique secondary index for the companyname on the company tablethanxs
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