![]() ![]() ![]() How to Select Most Recent Record for Each User Where product_sales.product=max_sales.productĪnd product_sales.order_date=max_sales.order_date ( select product,max(order_date) as order_date mysql> select product_sales.* from product_sales, Now that we know the most recent date for each group, we join this result with our original table to get latest record by date group. mysql> select product,max(order_date) from product_sales group by product First we use GROUP BY to get most recent date for each group. Let’s say you want to get last record in each group, that is, for each product. Mysql> insert into product_sales(product,order_date, sale)īonus Read : How to Get Record with Max Value in MySQL mysql> create table product_sales(product varchar(255),order_date date, sale int) Let’s say you have a table product_sales(product, order_date,sale) that contains sales data for multiple products. Here are the steps to get last record in each group in MySQL. How To Get Last Record In Each Group In MySQL You can also use it to select last row for each group in PostgreSQL, SQL Server & Oracle. Here’s the SQL query to get last record in each group in MySQL, since there is no built-in function for it. SQL Tip: LEFT JOINs and WHERE clauses.Sometimes you may need to select most recent record or get latest record for each date,user, id or any other group.SQL Tip: The "query()" and "value()" methods (XML). ![]() SQL Tip: Return only latest record by date.SQL Tip: Creating a Grand Total (and additional subtotals).I put this little example together for you Doug…copy/paste this and see what I mean:ĭECLARE table ( MachineName varchar(25) NOT NULL So, here’s another generalized query to help explain how that could be achieved. In addition, it was suggested to have a sample query for cases when you might want to join this to other tables. This is so that you can tell SQL which record from the main table you want to retrieve. The sub query is then joined to the same table on the entity AND the dates. It also occurred to me that perhaps I should give a quick explanation of what is going on with the sample query: The sub query is written to get the max date for each entity (in this case Machine). When creating an aggregate (such as MAX) you don’t want to group by the value you want to find the max of. It was grouping by the date desired in the MAX aggregate. After looking at the sub query I noticed the issue was with the GROUP BY portion of the query. Today someone reached out to ask why they couldn’t get this to work for them in their query. The following generalized query will allow you to do this. The record you want to see is the one with the latest information (determined by the date column).You don’t want to see multiple records for a given machine meaning, you want to only return one record per machine.The table has a date specifying the time of the record insert (or something like an inventory scan time).You have a table that can have multiple records for a given entity (such as a machine).I’ve been asked this a couple times over the past few months and again today so I thought I’d send it out in hopes that others will benefit from this. Note: there are multiple ways to do this but at the time I originally wrote this I only wrote about this one. I have left this as originally written but have updated formatting for my WordPress theme. This was originally posted to my internal (to Microsoft) blog on as part of a series I called ‘SQL Tips’ for coworkers based on an email distribution list I sent out before the internal blog. ![]()
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