select from view -> update OR insert into table - mysql

Question

I want to select data from a mysql-view which collects and joins data from "federated"-tables.
This data should be inserted into a table which looks very similar to the view.
an example would be:
table where data needs to be inserted or updated:
insertTable
+----+-----------+------+-------------+
| id | foreignId | data | foreignData |
+----+-----------+------+-------------+
| 1 | a | 111 | aaa |
| 2 | b | 222 | bbb |
+----+-----------+------+-------------+
the view where the data comes from:
dataView
+-----------+-------------+
| foreignId | foreignData |
+-----------+-------------+
| a | AAA |
| b | BBB |
| c | CCC |
+-----------+-------------+
insertTable
+----+-----------+------+-------------+
| id | foreignId | data | foreignData |
+----+-----------+------+-------------+
| 1 | a | 111 | AAA |
| 2 | b | 222 | BBB |
| 3 | b | | CCC |
+----+-----------+------+-------------+
and at this point i think i need a stored procedure which does following written in pseudo code
$result = SELECT * FROM dataView;
foreach $result as $row {
if(SELECT COUNT(*) FROM inserTable WHERE foreignId=$row[foreignId]>0)
UPDATE insertView SET foreignData = $row[foreignData] WHERE foreignId=$row[foreignId];
else
INSERT INTO insertView (id, foreignId, foreignData) VALUES (null,$row[foreignId],$row[foreignData];
}

Answer 1

You can use REPLACE query.
REPLACE INTO insertView (id, foreignId, foreignData) VALUES (null,$row[foreignId],$row[foreignData];
From mysql documentation
REPLACE works exactly like INSERT, except that if an old row in the
table has the same value as a new row for a PRIMARY KEY or a UNIQUE
index, the old row is deleted before the new row is inserted. See
Section 13.2.5, “INSERT Syntax”.
PRIMARY KEY or a UNIQUE index not specified it will insert a new row.
So no need to SELECT checking.

Answer 2

The magic which is ideal for this problem was ON DUPLICATE KEY UPDATE
In my example the solution would look like this:
INSERT INTO insertTable
(
`foreignId`,
`foreignData`
)
SELECT
`dataView`.`foreignId`,
`dataView`.`foreignData`
FROM
`dataView`
ON DUPLICATE KEY UPDATE
`foreignId` = `dataView`.`foreignId`,
`foreignData` = `dataView`.`foreignData`;