You can't specify target table for update in FROM clause

I have a simple mysql table:

CREATE TABLE IF NOT EXISTS `pers` (
  `persID` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(35) NOT NULL,
  `gehalt` int(11) NOT NULL,
  `chefID` int(11) DEFAULT NULL,
  PRIMARY KEY (`persID`)
) ENGINE=MyISAM  DEFAULT CHARSET=latin1 AUTO_INCREMENT=4 ;

INSERT INTO `pers` (`persID`, `name`, `gehalt`, `chefID`) VALUES
(1, 'blb', 1000, 3),
(2, 'as', 1000, 3),
(3, 'chef', 1040, NULL);

I tried to run following update, but I get only the error 1093:

UPDATE pers P 
SET P.gehalt = P.gehalt * 1.05 
WHERE (P.chefID IS NOT NULL 
OR gehalt < 
(SELECT (
    SELECT MAX(gehalt * 1.05) 
    FROM pers MA 
    WHERE MA.chefID = MA.chefID) 
    AS _pers
))

I searched for the error and found from mysql following page http://dev.mysql.com/doc/refman/5.1/en/subquery-restrictions.html, but it doesn't help me.

What shall I do to correct the sql query?

---

The problem is that MySQL, for whatever inane reason, doesn't allow you to write queries like this:

UPDATE myTable
SET myTable.A =
(
    SELECT B
    FROM myTable
    INNER JOIN ...
)

That is, if you're doing an UPDATE / INSERT / DELETE on a table, you can't reference that table in an inner query (you can however reference a field from that outer table...)

---

The solution is to replace the instance of myTable in the sub-query with (SELECT * FROM myTable) , like this

UPDATE myTable
SET myTable.A =
(
    SELECT B
    FROM (SELECT * FROM myTable) AS something
    INNER JOIN ...
)

This apparently causes the necessary fields to be implicitly copied into a temporary table, so it's allowed.

I found this solution here. A note from that article:

You don't want to just SELECT * FROM table in the subquery in real life; I just wanted to keep the examples simple. In reality, you should only be selecting the columns you need in that innermost query, and adding a good WHERE clause to limit the results, too.

---

You can make this in three steps:

CREATE TABLE test2 AS
SELECT PersId 
FROM pers p
WHERE (
  chefID IS NOT NULL 
  OR gehalt < (
    SELECT MAX (
      gehalt * 1.05
    )
    FROM pers MA
    WHERE MA.chefID = p.chefID
  )
)

...

UPDATE pers P
SET P.gehalt = P.gehalt * 1.05
WHERE PersId
IN (
  SELECT PersId
  FROM test2
)
DROP TABLE test2;

or

UPDATE Pers P, (
  SELECT PersId
  FROM pers p
  WHERE (
   chefID IS NOT NULL 
   OR gehalt < (
     SELECT MAX (
       gehalt * 1.05
     )
     FROM pers MA
     WHERE MA.chefID = p.chefID
   )
 )
) t
SET P.gehalt = P.gehalt * 1.05
WHERE p.PersId = t.PersId

---

Make a temporary table (tempP) from a subquery

UPDATE pers P 
SET P.gehalt = P.gehalt * 1.05 
WHERE P.persID IN (
    SELECT tempP.tempId
    FROM (
        SELECT persID as tempId
        FROM pers P
        WHERE
            P.chefID IS NOT NULL OR gehalt < 
                (SELECT (
                    SELECT MAX(gehalt * 1.05) 
                    FROM pers MA 
                    WHERE MA.chefID = MA.chefID) 
                    AS _pers
                )
    ) AS tempP
)

I've introduced a separate name (alias) and give a new name to 'persID' column for temporary table

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