Top "Duplicates" questions

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

Remove duplicates from a List<T> in C#

Anyone have a quick method for de-duplicating a generic List in C#?

c# list generics duplicates
Fastest way to duplicate an array in JavaScript - slice vs. 'for' loop

In order to duplicate an array in JavaScript: which of the following is faster to use? ###Slice method var dup_…

javascript arrays duplicates copy slice
How do you remove duplicates from a list whilst preserving order?

Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use …

python list duplicates unique
Find duplicate lines in a file and count how many time each line was duplicated?

Suppose I have a file similar to the following: 123 123 234 234 123 345 I would like to find how many times '123' was …

file count find duplicates lines
Finding duplicate rows in SQL Server

I have a SQL Server database of organizations, and there are many duplicate rows. I want to run a select …

sql sql-server duplicates
Remove duplicates from an array of objects in JavaScript

I have an object that contains an array of objects. things = new Object(); things.thing = new Array(); things.thing.push({…

javascript arrays object duplicates
Delete all Duplicate Rows except for One in MySQL?

How would I delete all duplicate data from a MySQL Table? For example, with the following data: SELECT * FROM names; +…

mysql sql duplicates
Removing duplicate rows from table in Oracle

I'm testing something in Oracle and populated a table with some sample data, but in the process I accidentally loaded …

sql oracle duplicates delete-row
How to select records without duplicate on just one field in SQL?

I have a table with 3 columns like this: +------------+---------------+-------+ | Country_id | country_title | State | +------------+---------------+-------+ There …

sql select duplicates distinct
Remove duplicate rows in MySQL

I have a table with the following fields: id (Unique) url (Unique) title company site_id Now, I need to …

mysql sql duplicates