How to Retrieve Rows with Minimum Values for Each Unique Identifier in SQL?

SQL efficient screening: Get the minimum value of each unique identifier

In database management, it is often necessary to extract records with unique values ​​and its corresponding minimum values. Suppose there is a form containing the unique identifier column and associated values. The goal is to retrieve the rows corresponding to the minimum value from each unique identifier.

Challenge

Consider the following table:

The goal is to find the minimum

line corresponding to each unique

id	game	point
1	x	5
1	z	4
2	y	6
3	x	2
3	y	5
3	z	8

value. The expected output is as follows:

game Solution point

id	game	point
1	z	4
2	y	6
3	x	2

You can use the following SQL query to achieve this:

Explanation

<code class="language-sql">SELECT tbl.*
FROM TableName tbl
INNER JOIN (
    SELECT Id, MIN(Point) AS MinPoint
    FROM TableName
    GROUP BY Id
) tbl1 ON tbl1.id = tbl.id
WHERE tbl1.MinPoint = tbl.Point;</code>

Internal query calculates the minimum

value of each unique and stores the result in the derivative table .

The main inquiry will connect the original table
• with Id according to the public Point column. tbl1
In the end, it filter the result, only contains the minimum
• value (from Id) and the line of TableName in the original table. tbl1
• By using this query, you can efficiently retrieve the unique row of Point in the tbl1 group. Point

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