MySQL ON DUPLICATE KEY UPDATE for multiple rows insert in single query

Question

I have a SQL query where I want to insert multiple rows in single query. so I used something like:

$sql = "INSERT INTO beautiful (name, age)
  VALUES
  ('Helen', 24),
  ('Katrina', 21),
  ('Samia', 22),
  ('Hui Ling', 25),
  ('Yumie', 29)";

mysql_query( $sql, $conn );

The problem is when I execute this query, I want to check whether a UNIQUE key (which is not the PRIMARY KEY), e.g. 'name' above, should be checked and if such a 'name' already exists, the corresponding whole row should be updated otherwise inserted.

For instance, in the example below, if 'Katrina' is already present in the database, the whole row, irrespective of the number of fields, should be updated. Again if 'Samia' is not present, the row should be inserted.

I thought of using:

INSERT INTO beautiful (name, age)
      VALUES
      ('Helen', 24),
      ('Katrina', 21),
      ('Samia', 22),
      ('Hui Ling', 25),
      ('Yumie', 29) ON DUPLICATE KEY UPDATE

Here is the trap. I got stuck and confused about how to proceed. I have multiple rows to insert/update at a time. Please give me a direction. Thanks.

Solution 1

Beginning with MySQL 8.0.19 you can use an alias for that row (see reference).

INSERT INTO beautiful (name, age)
    VALUES
    ('Helen', 24),
    ('Katrina', 21),
    ('Samia', 22),
    ('Hui Ling', 25),
    ('Yumie', 29)
    AS new
ON DUPLICATE KEY UPDATE
    age = new.age
    ...

---

For earlier versions use the keyword VALUES (see reference, deprecated with MySQL 8.0.20).

INSERT INTO beautiful (name, age)
    VALUES
    ('Helen', 24),
    ('Katrina', 21),
    ('Samia', 22),
    ('Hui Ling', 25),
    ('Yumie', 29)
ON DUPLICATE KEY UPDATE
    age = VALUES(age),
     ...

Solution 2

INSERT INTO ... ON DUPLICATE KEY UPDATE will only work for MYSQL, not for SQL Server.

for SQL server, the way to work around this is to first declare a temp table, insert value to that temp table, and then use MERGE

Like this:

declare @Source table
(
name varchar(30),
age decimal(23,0)
)

insert into @Source VALUES
('Helen', 24),
('Katrina', 21),
('Samia', 22),
('Hui Ling', 25),
('Yumie', 29);


MERGE beautiful  AS Tg
using  @source as Sc
on tg.namet=sc.name 

when matched then update 
set tg.age=sc.age

when not matched then 
insert (name, age) VALUES
(SC.name, sc.age);

Comments

[Prashant]

Yes but using REPLACE the old row is deleted before the new row is inserted. I want to retain the old row for maintaining primary ids.

[a1ex07]

I didn't realize that retaining the old PK is somehow important to you... Surely, REPLACE won't work in this case...

[MLeFevre]

If you don't care about PK however, like in my case, this works perfectly.

[Oliver M Grech]

PS: "replace into" requires both delete and insert privileges!

[Ross]

and for the above mentioned delete/insert reasons, its also much slower in these instances.

[imVJ]

What if you want to update few columns? Replace will update all.

[phoenix]

Great suggestion. If you want to increment a value when duplicate, add this after the "ON DUPLICATE KEY UPDATE" part: total = total + VALUES( total )

[Simon]

Caution: The use of VALUES() to refer to the new row and columns is deprecated beginning with MySQL 8.0.20. See : dev.mysql.com/doc/refman/8.0/en/insert-on-duplicate.html

[Brandon]

Original question is specifically about MySQL

[harlekintiger]

Caution: Don't use the variable name new

[Peter Lang]

@harlekintiger They seem to use new in the manual that I linked. I don't work with MySQL though, so could you please elaborate why it should not be named new? Thank you!

[harlekintiger]

@PeterLang of course, I should've specified the first time. While it does work and won't throw an error, at least for now, in MySQL 'new' is a reserved keyword MySQL 8.0 Manual: 9.3 Keywords and Reserved Words