ERRORE: Errore 1215: Impossibile aggiungere vincolo di chiave esterna

Question

ottengo l'errore: ERRORE: Errore 1215: Impossibile aggiungere vincolo di chiave esterna

ho letto di altri simili argomenti e http://dev.mysql.com/doc/refman/5.7/en/create-table-foreign-keys.html, ovviamente, però non riesco a risolvere il problema.

Il codice viene generato come segue (e dovrebbe funzionare senza problemi maledizione):

SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0; 
SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0; 
SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='TRADITIONAL,ALLOW_INVALID_DATES'; 

CREATE SCHEMA IF NOT EXISTS `foilmaster` DEFAULT CHARACTER SET latin1 ; 
USE `foilmaster`; 

-- ----------------------------------------------------- 
-- Table `foilmaster`.`Company` 
-- ----------------------------------------------------- 

DROP TABLE IF EXISTS `foilmaster`.`Company` ; 

CREATE TABLE IF NOT EXISTS `foilmaster`.`Company` (
    `idCompany` MEDIUMINT(9) NOT NULL AUTO_INCREMENT , 
    `Name` VARCHAR(85) NOT NULL , 
    `Country` VARCHAR(35) NOT NULL , 
    `PotentialSaleScale` SMALLINT NOT NULL COMMENT '1-100 Where 1 is 1 Pallete a Month and 100 is 1 Truck a week' , 
    `DateAdded` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP , 
    PRIMARY KEY (`idCompany`) 
) ENGINE = InnoDB; 

-- ----------------------------------------------------- 
-- Table `foilmaster`.`ContactData` 
-- ----------------------------------------------------- 

DROP TABLE IF EXISTS `foilmaster`.`ContactData` ; 

CREATE TABLE IF NOT EXISTS `foilmaster`.`ContactData` (
    `idCompany` MEDIUMINT(9) NOT NULL , 
    `Phone` VARCHAR(45) NOT NULL , 
    INDEX `fk_ContactData_Company_idx` (`idCompany` ASC) , 
    PRIMARY KEY (`idCompany`) , 
    CONSTRAINT `fk_ContactData_Company` FOREIGN KEY (`idCompany`) 
     REFERENCES `foilmaster`.`Company` (`idCompany`) 
     ON DELETE NO ACTION 
     ON UPDATE NO ACTION 
    ) ENGINE = InnoDB; 

USE `foilmaster` ; 

SET SQL_MODE=@OLD_SQL_MODE; 
SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS; 
SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS; 

stato InnoDB mostra questo:

===================================== 
2013-05-26 13:07:32 460 INNODB MONITOR OUTPUT 
===================================== 
Per second averages calculated from the last 52 seconds 
----------------- 
BACKGROUND THREAD 
----------------- 
srv_master_thread loops: 8 srv_active, 0 srv_shutdown, 7450 srv_idle 
srv_master_thread log flush and writes: 7458 
---------- 
SEMAPHORES 
---------- 
OS WAIT ARRAY INFO: reservation count 20 
OS WAIT ARRAY INFO: signal count 19 
Mutex spin waits 2, rounds 0, OS waits 0 
RW-shared spins 19, rounds 570, OS waits 19 
RW-excl spins 1, rounds 30, OS waits 1 
Spin rounds per wait: 0.00 mutex, 30.00 RW-shared, 30.00 RW-excl 
------------------------ 
LATEST FOREIGN KEY ERROR 
------------------------ 
2013-05-26 13:07:16 f0c Error in foreign key constraint of table foilmaster/contactdata: 
there is no index in referenced table which would contain 
the columns as the first columns, or the data types in the 
referenced table do not match the ones in table. Constraint: 
, 
    CONSTRAINT "ID" FOREIGN KEY ("ID") REFERENCES "company" ("ID") 
The index in the foreign key in table is "PRIMARY" 
See http://dev.mysql.com/doc/refman/5.6/en/innodb-foreign-key-constraints.html 
for correct foreign key definition. 
------------ 
TRANSACTIONS 
------------ 
Trx id counter 3386 
Purge done for trx's n:o < 3386 undo n:o < 0 state: running but idle 
History list length 240 
LIST OF TRANSACTIONS FOR EACH SESSION: 
---TRANSACTION 0, not started 
MySQL thread id 12, OS thread handle 0x460, query id 394 localhost 127.0.0.1 root init 
SHOW ENGINE INNODB STATUS 
---TRANSACTION 0, not started 
MySQL thread id 2, OS thread handle 0x1560, query id 83 localhost 127.0.0.1 root cleaning up 
-------- 
FILE I/O 
-------- 
I/O thread 0 state: wait Windows aio (insert buffer thread) 
I/O thread 1 state: wait Windows aio (log thread) 
I/O thread 2 state: wait Windows aio (read thread) 
I/O thread 3 state: wait Windows aio (read thread) 
I/O thread 4 state: wait Windows aio (read thread) 
I/O thread 5 state: wait Windows aio (read thread) 
I/O thread 6 state: wait Windows aio (write thread) 
I/O thread 7 state: wait Windows aio (write thread) 
I/O thread 8 state: wait Windows aio (write thread) 
I/O thread 9 state: wait Windows aio (write thread) 
Pending normal aio reads: 0 [0, 0, 0, 0] , aio writes: 0 [0, 0, 0, 0] , 
ibuf aio reads: 0, log i/o's: 0, sync i/o's: 0 
Pending flushes (fsync) log: 0; buffer pool: 0 
405 OS file reads, 168 OS file writes, 82 OS fsyncs 
0.00 reads/s, 0 avg bytes/read, 0.37 writes/s, 0.17 fsyncs/s 
------------------------------------- 
INSERT BUFFER AND ADAPTIVE HASH INDEX 
------------------------------------- 
Ibuf: size 1, free list len 0, seg size 2, 0 merges 
merged operations: 
insert 0, delete mark 0, delete 0 
discarded operations: 
insert 0, delete mark 0, delete 0 
Hash table size 58207, node heap has 0 buffer(s) 
0.00 hash searches/s, 0.81 non-hash searches/s 
--- 
LOG 
--- 
Log sequence number 8995932 
Log flushed up to 8995932 
Pages flushed up to 8995932 
Last checkpoint at 8995932 
0 pending log writes, 0 pending chkp writes 
43 log i/o's done, 0.08 log i/o's/second 
---------------------- 
BUFFER POOL AND MEMORY 
---------------------- 
Total memory allocated 30048256; in additional pool allocated 0 
Dictionary memory allocated 55489 
Buffer pool size 1792 
Free buffers  1369 
Database pages  423 
Old database pages 0 
Modified db pages 0 
Pending reads 0 
Pending writes: LRU 0, flush list 0 single page 0 
Pages made young 0, not young 0 
0.00 youngs/s, 0.00 non-youngs/s 
Pages read 391, created 32, written 97 
0.00 reads/s, 0.08 creates/s, 0.21 writes/s 
Buffer pool hit rate 1000/1000, young-making rate 0/1000 not 0/1000 
Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s 
LRU len: 423, unzip_LRU len: 0 
I/O sum[0]:cur[0], unzip sum[0]:cur[0] 
-------------- 
ROW OPERATIONS 
-------------- 
0 queries inside InnoDB, 0 queries in queue 
0 read views open inside InnoDB 
Main thread id 2672, state: sleeping 
Number of rows inserted 0, updated 0, deleted 0, read 0 
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s 
---------------------------- 
END OF INNODB MONITOR OUTPUT 
============================ 

trascorso 2 ore che finora ... semplicemente fissando: P

Answer 1

Entrambe le risposte erano sbagliate. Qual era la soluzione?

Ho spostato questa riga verso l'alto DROP TABLE SE EXISTS foilmaster. ContactData;

Inoltre, spuntando la casella di controllo DROP schema funziona anche.

ho iniziato chiedendo perché è il modo in cui è ... e si è conclusa con il solito "Sto bene fintanto che funziona" :)