sql - 如何在Oracle的表中找到重复的值？(How do I find duplicate values in a table in Oracle?)

Question

What's the simplest SQL statement that will return the duplicate values for a given column and the count of their occurrences in an Oracle database table?

(什么是最简单的SQL语句，该语句将返回给定列的重复值及其在Oracle数据库表中的出现次数？)

For example: I have a JOBS table with the column JOB_NUMBER .

(例如：我有一个JOBS表，其JOB_NUMBER 。)

How can I find out if I have any duplicate JOB_NUMBER s, and how many times they're duplicated?

(如何确定我是否有重复的JOB_NUMBER ，以及它们重复了多少次？)

  ask by Andrew translate from so

Answer 1

SELECT column_name, COUNT(column_name)
FROM table_name
GROUP BY column_name
HAVING COUNT(column_name) > 1;