If a supplier_id value in the suppliers table does not exist in the orders table, all fields in the orders table will display as in the result set. This LEFT OUTER JOIN example would return all rows from the suppliers table and only those rows from the orders table where the joined fields are equal. Here is an example of a MySQL LEFT OUTER JOIN: SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date ![]() The MySQL LEFT OUTER JOIN would return the all records from table1 and only those records from table2 that intersect with table1. In this visual diagram, the MySQL LEFT OUTER JOIN returns the shaded area: In some databases, the LEFT OUTER JOIN keywords are replaced with LEFT JOIN. The syntax for the LEFT OUTER JOIN in MySQL is: SELECT columns This type of join returns all rows from the LEFT-hand table specified in the ON condition and only those rows from the other table where the joined fields are equal (join condition is met). ![]() It contains the following data:Īnother type of join is called a MySQL LEFT OUTER JOIN. We have a table called suppliers with two fields (supplier_id and supplier_name). Let's look at some data to explain how the INNER JOINS work: This MySQL INNER JOIN example would return all rows from the suppliers and orders tables where there is a matching supplier_id value in both the suppliers and orders tables. ON suppliers.supplier_id = orders.supplier_id Here is an example of a MySQL INNER JOIN: SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date The MySQL INNER JOIN would return the records where table1 and table2 intersect. In this visual diagram, the MySQL INNER JOIN returns the shaded area: The syntax for the INNER JOIN in MySQL is: SELECT columns MySQL INNER JOINS return all rows from multiple tables where the join condition is met. SET = CONCAT('SELECT o.Chances are, you've already written a statement that uses a MySQL INNER JOIN. WHERE o1.id=(SELECT owner_id FROM (SELECT owner_id, COUNT(1) AS cnt FROM phones GROUP BY owner_id) c ORDER BY cnt DESC LIMIT 1)) phones INNER JOIN phones p ON o1.id = p.owner_id ) INTO (SELECT o1.id, p.numbers, := + 1 AS rn Query to return records for all owners: SET = NULL ĬONCAT('(SELECT numbers FROM phones WHERE owner_id = o.id ORDER BY numbers LIMIT 1 OFFSET ',rn - 1,' ) AS numbers', rn) SET = CONCAT('SELECT id, ', ' FROM owner WHERE id = 1') ) INTO (SELECT o.id, p.numbers, := + 1 AS rn SET = NULL ĬONCAT('(SELECT numbers FROM phones WHERE owner_id = ',id, ' ORDER BY numbers LIMIT 1 OFFSET ',rn - 1,' ) AS numbers', rn) The query below returns exactly what you described in your question but I doubt this is what you really need. There can be around 10 phone numbers per owner. (Each phone number in a dedicated column) and they can be different. I want to get for each owner (t1) every phone number (t2) associated to him, in a single row with multiple columns. This Q & A MySQL single table static and dynamic pivot doesn't resolve the issue since "Kode 1" or "Kode 2" are the different phone numbers for me. Getting the following result o.id p.numbers The goal is to get a json ready to be imported in a MongoDB database. ![]() ![]() In this example the expected result is to have for each owner all the associated phone numbers in a single row, starting from a multiple rows table. In a one-to-many relationship query, I would have a single row and dynamic multiple columns.
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