Breaking the Law: Primary Keys in SQL Server - CodeProject
In the old days of OLEDB and ADO, when the database driver could not get any key information concerning the Recordset, it would try to create its own key. I am not talking about poor designs from an academic point of view; these sub-standard designs don't work because they are a performance, programming, scalability and maintenance nightmare
I have now successfully produced a script which drops all the relevant constraints, identifies and deletes the duplicate keys and then re-creates all the constraints without loss of the original data (we think :-)). Should I be looking at something other than the column values?I have passed your suggestions for identifying the root cause of the problem to the customer and requested details of the exact version of SQL Server they are using and will post details here when they become available
Deleting large number of rows from a table in a VLDB - SQLServerCentral
You may read more about these here: TOP (Transact-SQL) Limiting Result Sets by TOP and PERCENT Essentially, the prime difference between the TOP and ROWCOUT is that the query optimizer can use the value of expression in the TOP clause as part of generating an execution plan for a query. Building the test data I will provide the entire script to start from a new database below (as such, the number of rows we will be purging will be similar as can be seen from the statistics mentioned after the script)
SQL Server and Duplicate Indexes - CodeProject
Introduction Everyone should know that indexes on a database are both useful and to be feared! One of the most common things I've come across in my years of working on database backed products is that people grossly underestimate the impact of adding indexes. Firstly, unless you're using a real data (you ran the trace during a typical period on you're live production systems and it included ALL the usage that will happen), the suggestions won't be exact
Newest Questions - Database Administrators Stack Exchange
sql-server connections informatica sql-server-core multi-thread asked 1 hour ago MacGyver 55931325 0 votes 0answers 5 views AlwaysOn Availability Listener only working on one node We are creating an new SQL 2014 AlwaysOn Availability Group called SQLProd with 3 nodes: SQLPrimary SQLReports SQLDR SQLPrimary is the server we are going to host the primary replica on. mongodb mongodb-3.0 asked 9 hours ago Baruch Oxman 1011 -1 votes 2answers 24 views How to Interpret Trace Flag 1222 deadlock please guide me how to read this graph to figure out what is cause for this deadlock
sql sql-server-2008 performance asked 16 hours ago user2173353 1412 0 votes 1answer 39 views SQL Server : Tracking a slow running query on completion Am trying to work on script for slow-running queries. sql-server-2008 trigger asked Jul 18 at 13:22 ManOnAMission 1135 2 votes 1answer 30 views Select columns dynamically from sql server table Lets say I have a table that actually store record which looks like Create Table dbo.Info ( SN int primary key identity(1,1), FirstName nvarchar(50) not null, LastName nvarchar(50) not null, ..
Violation Of primary key constraints, Cannot insert a duplicate key in object
Furthermore, if there are 3 matching rows in statement and 5 rows in wonderlife, you will get 15 rows in total, because these rows will multiply with each other.How you should fix it? You need to review your business requirements? What are you trying to achieve? And of course you need to review the cardinality of all dependencies in the query. The value that is causing this error is (128503).I have queried the repaidid 128503 in the database to see if it is a duplicate but could not find any duplicate.EOOf course you will not find a duplicate key (128503) in the database because of the primary key.Hint:Create a temp table with the same structure as the one you're inserting in and without primary key
Type into the console: select count() from TheTable and select distinct from TheTable The 1st command tells you how many total records you have in the table, and the 2nd command tells you how many duplicates you have. The total count of the original table should be the difference between the number counted before the delete query and the number deleted from the table
SQL Server Forums - Copy rows into the same table with new primary key
You have added repeating values.If one row is updated, will the other row with DUPLICATE data also need updating? To get to 1st Normal Form, repeating columns should be in tableA and tableB has a column which references TableA
MsSQL Miscellaneous Delete duplicate rows without primary key in ms sql server Tutorial
MsSQL Miscellaneous Delete duplicate rows without primary key in ms sql server Tutorial MsSQL Miscellaneous Delete duplicate rows without primary key in ms sql server Tutorial To view the tutorial, "Delete duplicate rows without primary key in ms sql server", please follow the link below: MsSQL Miscellaneous Delete duplicate rows without primary key in ms sql server Tutorial Go here for more MsSQL Tutorials
sql server 2005 - Delete duplicate records from a SQL table without a primary key - Stack Overflow
Like Josh said - even if you know the duplicates, deleting them will be impossile since you cannot actually refer to a specific record if it is an exact duplicate of another record
select * from mytable union select * from mytable, thsi query returns the exact records, and i guess we can use this data to build a new table or replacing the previous one. I need to get rid of the duplications, meaning that when names are shown more than once for a given month and year, I only want one of the duplicated intervention records to show up
We extensively use GROUP BY and we all know problem with GROUP BY (We should have all selected column from select clause in group by clause, other wise we cannot use group by). The problem is: the system by mistake inserted duplicate data in R2-R5 (R1 is PK assuem autonumber) and in one of these duplicates R6 and R7 are also filled
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