Top "Duplicate-removal" questions

The "duplicates" tag concerns detecting and/or dealing with multiple instances of items in collections.

C# LINQ find duplicates in List

Using LINQ, from a List<int>, how can I retrieve a list that contains entries repeated more than …

linq list duplicate-removal
Delete duplicate records from a SQL table without a primary key

I have the below table with the below records in it create table employee ( EmpId number, EmpName varchar2(10), EmpSSN varchar2(11) ); …

sql sql-server-2005 tsql duplicate-removal
Eliminating duplicate values based on only one column of the table

My query: SELECT sites.siteName, sites.siteIP, history.date FROM sites INNER JOIN history ON sites.siteName = history.siteName ORDER …

sql sql-server distinct inner-join duplicate-removal
How can I delete one of two perfectly identical rows?

I am cleaning out a database table without a primary key (I know, I know, what were they thinking?). I …

sql duplicate-removal
How to delete duplicate entries?

I have to add a unique constraint to an existing table. This is fine except that the table has millions …

sql postgresql duplicate-removal unique-constraint sql-delete
Delete rows that exist in another data frame?

I have the two following data frames (example): df1: name profile type strand A 4.5 1 + B 3.2 1 + C 5.5 1 + D 14.0 1 - E 45.1 1 - …

r dataframe duplicate-removal delete-row corresponding-records
Remove Duplicate Entries in a C++ Vector

Just want to remove duplicates. Pool is vector<pair<string, int>> but I seem to miss …

c++ vector duplicate-removal erase
Postgres: left join with order by and limit 1

I have the situation: Table1 has a list of companies. Table2 has a list of addresses. Table3 is a N …

postgresql sql-order-by left-join foreign-key-relationship duplicate-removal
How to delete duplicate rows in sybase, when you have no unique key?

Yes, you can find similar questions numerous times, but: the most elegant solutions posted here, work for SQL Server, but …

sql sybase duplicate-removal sqlanywhere
MySQL insert on duplicate key; delete?

Is there a way of removing record on duplicate key in MySQL? Say we have a record in the database …

mysql key duplicate-removal sql-delete