UPDATE con SELECT anidado

[huesos52]

tenes razón.

Mira esto:

Código sql:

mysql> CREATE TABLE ventas(factura INTEGER PRIMARY KEY AUTO_INCREMENT,cajatotal INTEGER);
Query OK, 0 ROWS affected (0.02 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.02 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> INSERT INTO ventas (cajatotal) VALUES(4);
Query OK, 1 ROW affected (0.00 sec)
 
mysql> SELECT *FROM ventas;
+---------+-----------+
| factura | cajatotal |
+---------+-----------+
|       1 |         4 |
|       2 |         4 |
|       3 |         4 |
|       4 |         4 |
|       5 |         4 |
|       6 |         4 |
|       7 |         4 |
|       8 |         4 |
+---------+-----------+
8 ROWS IN SET (0.00 sec)
 
mysql> UPDATE ventas SET cajatotal=2 WHERE factura = last_insert_id();
Query OK, 1 ROW affected (0.00 sec)
ROWS matched: 1  Changed: 1  Warnings: 0
 
mysql> SELECT *FROM ventas;
+---------+-----------+
| factura | cajatotal |
+---------+-----------+
|       1 |         4 |
|       2 |         4 |
|       3 |         4 |
|       4 |         4 |
|       5 |         4 |
|       6 |         4 |
|       7 |         4 |
|       8 |         2 |
+---------+-----------+
8 ROWS IN SET (0.00 sec)
 
mysql>
 

Te sirve?