获取所有唯一记录及其对应的列 [英] get all unique records and their corresponding column

问题描述

是否可以在数据库中获取所有唯一记录及其对应的列?

Is it possible to get all unique records as well as their corresponding column in a database?

类似:

SELECT DISTINCT *
FROM table_name
?where?

我想获取所有唯一记录及其对应的列.

I want to get all unique records with their corresponding column.

我试过了:

SELECT distinct(column_name), other_column
FROM table_name
?where?

我仍然收到重复的记录.

I still get duplicate records.

我试过了:

SELECT distinct(column_name)
    FROM table_name
    ?where?

我得到唯一记录但不完整的列.如何获取所有带有列的唯一记录?

I get unique records but incomplete column. How can I get all unique records w/ their column?

推荐答案

您在寻找这样的东西吗?

Are you looking for something like this?

SELECT t.*
  FROM
(
  SELECT MIN(pk_id) pk_id
    FROM table_name
   GROUP BY fk_id
) q JOIN table_name t
    ON q.pk_id = t.pk_id

这是SQLFiddle演示

Here is SQLFiddle demo

在 Postgres 中你可以使用 DISTINCT ON

In Postgres you can use DISTINCT ON

SELECT DISTINCT ON (fk_id) t.*
  FROM table_name t
 ORDER BY fk_id

这是SQLFiddle 演示

Here is SQLFiddle demo

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