The above is purely an example scenario to easily explain the joins I am trying to achieve and does not reflect an actual system design. However, as a Customer may have multiple Addresses will the customer only be counted in the State of the most recent Address record? LEFT JOIN Address a ON a.CustomerID = c.CustomerID INNER JOIN Customer c ON c.CustomerID = p.CustomerID I would normally do something like: SELECT a.State, count(c.CustomerID) Therefore I'm not interested in any previous Address records for the Customer, only the most Recent (determined by AddressID). How do I join on 'most recent' records Ive got two tables in a SQL Server 2000 database joined by a parent child relationship. In MySQL, youd use select from mytable order by datecol desc limit 1 Note that this is a quite slow operation even if theres an index on datecol as it. SELECT tbl.MachineName ,tbl.DateColumn ,tbl.Column3 -,tbl. Such as "How many customers last received a product in each State?". The record you want to see is the one with the latest information (determined by the date column) The following generalized query will allow you to do this. What I would like to do is to list the number of customers for each State where the State is determined by the most recent Address record. Product (ProductID, CustomerID, Description)Ī customer can have multiple delivery addresses and mulitple products. ) ENGINE=InnoDB AUTO_INCREMENT=10 DEFAULT CHARSET=utf8 A join is a method of linking data between one or more tables based on values of the common column between the tables. Also, the dates you're showing don't match how sql server normally formats dates. SELECT ID, Status, MAX (date) FROM table WHERE status'active' / optional / GROUP BY ID, Status.
MYSQL JOIN LATEST RECORD HOW TO
Insert into `tableA`(`id`,`fullname`,`social_num`,`email`) values (1,'David TABLE `tableB` ( how to join them together, so that, i get the latest record on tableA and latest record on tableB link by socialnum i tried following sql, it work: SELECT FROM tableA LEFT JOIN tableB ON tableA.socialnum tableB.socialnum WHERE tableA.id IN (SELECT MAX (id) AS id FROM tableA GROUP BY socialnum) AND tableB.id IN (SELECT MAX (id) AS id. I only see one, and you don't need to join it to anything to get your desired results.
MYSQL JOIN LATEST RECORD FULL
Note that MySQL hasn’t supported the FULL OUTER JOIN yet. The join clause is used in the SELECT statement appeared after the FROM clause. ) ENGINE=InnoDB AUTO_INCREMENT=13 DEFAULT CHARSET=utf8 Cross join To join tables, you use the cross join, inner join, left join, or right join clause. LEFT JOIN tableB ON tableA.social_num = tableB.social_numīut how do i show all of other user from tableA togather as well, like Morris Q How to join them together, so that, i get the latest record on tableA and latest record on tableB link by social_num? So you need to do something like this: SELECT a.
MYSQL JOIN LATEST RECORD TRIAL
I manage to get the latest record by auto increment id by using the following sql for tableA and tableB: SELECT * 1 Answer Sorted by: 0 Without access to the specifics of your tables, the problem you face is knowing 'the most recent' trial (in table B) In many rdbms one can use ROWNUMBER () to solve this problem, but as yet MySQL does not supply that useful function. I had 2 table, tableA and tableB looking like this: This question has been asked at here as well.
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