Mysql create table with multiple foreign key on delete set null - mysql

Question

I am trying to create a database with multiple foreign keys with delete/ update constraints, but I got a error code 1005 with following sql scripts:
CREATE TABLE Worker (
WorkerID smallint auto_increment,
WorkerType varchar(45) NOT NULL,
WorkerName varchar(45) NOT NULL,
Position varchar(45) NOT NULL,
TaxFileNumber int NOT NULL,
Address varchar(100) ,
Phone varchar(20) ,
SupervisorID smallint ,
PRIMARY KEY (WorkerID),
FOREIGN KEY (SupervisorID) REFERENCES Worker(WorkerID)
ON DELETE SET NULL
ON UPDATE CASCADE
)Engine=InnoDB;
CREATE TABLE Grape (
GrapeID smallint NOT NULL,
GrapeType varchar(45) NOT NULL,
JuiceConversionRatio int,
StorageContainer ENUM('Stainless Steel Tank','Oak Barrel'),
AgingRequirement int,
PRIMARY KEY (GrapeID)
)Engine=InnoDB;
CREATE TABLE Vineyard (
VineyardID smallint auto_increment,
VineyardName VARCHAR(45) NOT NULL,
FarmerID smallint NOT NULL,
GrapeID smallint NOT NULL,
ComeFrom varchar(45) NOT NULL,
HarvestedAmount int,
RipenessPercent int,
PRIMARY KEY (VineyardID),
FOREIGN KEY (FarmerID) REFERENCES Worker(WorkerID)
ON DELETE SET NULL
ON UPDATE CASCADE,
FOREIGN KEY (GrapeID) REFERENCES Grape(GrapeID)
ON DELETE SET NULL
ON UPDATE CASCADE
)Engine=InnoDB;
The error code says that fail to create the Vineyard table, I just want to know the proper format for creating multiple foreign keys with delete/update control.

Answer 1

Your foreign key rule is ON DELETE SET NULL but your column definition is NOT NULL.
Either change your column definition and remove the NOT NULL part or overthink your foreign key rule. That works:
CREATE TABLE Vineyard (
VineyardID smallint auto_increment,
VineyardName VARCHAR(45) NOT NULL,
FarmerID smallint,
GrapeID smallint,
ComeFrom varchar(45) NOT NULL,
HarvestedAmount int,
RipenessPercent int,
PRIMARY KEY (VineyardID),
FOREIGN KEY (FarmerID) REFERENCES Worker(WorkerID)
ON DELETE SET NULL
ON UPDATE CASCADE,
FOREIGN KEY (GrapeID) REFERENCES Grape(GrapeID)
ON DELETE SET NULL
ON UPDATE CASCADE
)Engine=InnoDB;
SQLFiddle demo

Answer 2

Try with create table(innoDB enginer) without foreign key and use the update table with constraint syntax, for example:
ALTER TABLE `vineyard`
ADD CONSTRAINT `relation_farmer_has_many_vineyards`
FOREIGN KEY (`farmer_id`)
REFERENCES `worker` (`worker_id`)
ON DELETE SET NULL
ON UPDATE CASCADE;
Reference:
http://dev.mysql.com/doc/refman/5.6/en/innodb-foreign-key-constraints.html
Trick: is not recommended to use capital letters(or camel case) in the names of the tables that the behavior differs from the operating system being used:
http://dev.mysql.com/doc/refman/5.1/en/identifier-case-sensitivity.html

Answer 3

Visit :
https://developer.android.com/training/basics/data-storage/databases.html#DefineContract
Cursor c = db.query(
FeedEntry.TABLE_NAME, // The table to query
projection, // The columns to return
selection, // The columns for the WHERE clause
selectionArgs, // The values for the WHERE clause
null, // don't group the rows
null, // don't filter by row groups
sortOrder // The sort order
);

Answer 4

Visit :
http://dev.mysql.com/doc/refman/5.5/en/innodb-foreign-key-constraints.html
CREATE TABLE `ffxi_characterJob` (
`serverID` int(11) NOT NULL,
`userid` int(10)unsigned NOT NULL,
`characterName` varchar(255) NOT NULL,
`jobAbbr` char(4) NOT NULL,
`jobLevel` int(11) default '0',
PRIMARY KEY (`serverID`,`userid`,`characterName`,`jobAbbr`),
INDEX (`jobAbbr`),
CONSTRAINT FOREIGN KEY (`serverID`,`userid`,`characterName`) REFERENCES `ffxi_characters` (`serverID`,`userid`,`characterName`)
ON DELETE CASCADE ON UPDATE CASCADE,
CONSTRAINT FOREIGN KEY (`jobAbbr`) REFERENCES `ffxi_jobType` (`jobAbbr`) ON DELETE CASCADE ON UPDATE CASCADE
) TYPE=InnoDB;