I need to remove duplicate rows from a fairly large SQL Server table (i.e. 300,000+ rows). The rows, of course, will not be perfect duplicates because of the existence of the RowID identity field.
9 It can be done by many ways in sql server the most simplest way to do so is: Insert the distinct rows from the duplicate rows table to new temporary table. Then delete all the data from duplicate rows table then insert all data from temporary table which has no duplicates as shown below.
Also indices of duplicates should be identified. Self join is a good option but to have a faster function it is better to first find rows that have duplicates and then join with original table for finding id of duplicated rows. Finally order by any column except id to have duplicated rows near each other.
Can you clarify what precision of date you start considering dates duplicate - day, hour, minute? In any case, you'll probably want to floor your datetime field. You didn't indicate which field is preferred when removing duplicates, so this query will prefer the last name in alphabetical order.
If you're looking for a way to remove duplicates, yet you have a foreign key pointing to the table with duplicates, you could take the following approach using a slow yet effective cursor. It will relocate the duplicate keys on the foreign key table.
3 You can use the in SQL Server to get the distinct records only. Apart from this you can also use the function to get the distinct result by assigning the numbers to a result set. The syntax of row_number() is as shown below.
I have a table with say 3 columns. There's no primary key so there can be duplicate rows. I need to just keep one and delete the others. Any idea how to do this is Sql Server?
0 table has duplicate rows and may be some rows have no duplicate rows then it keep one rows if have duplicate or single in a table. table has two column id and name if we have to remove duplicate name from table and keep one. Its Work Fine at My end You have to Use this query.
SELECT title, site_id, location, id, count( * ) FROM jobs GROUP BY site_id, company, title, location HAVING count( * ) >1 After running this query, I can remove duplicates using a server side script. But, I want to know if this can be done only using SQL query.
