mysql remove foreign key constraint

1-- On Create
2CREATE TABLE tableName (
3    ID INT,
4    SomeEntityID INT,
5    PRIMARY KEY (ID),
6    FOREIGN KEY (SomeEntityID)
7        REFERENCES SomeEntityTable(ID)
8        ON DELETE CASCADE
9);
10
11-- On Alter, if the column already exists but has no FK
12ALTER TABLE
13  tableName
14ADD
15  FOREIGN KEY (SomeEntityID) REFERENCES SomeEntityTable(ID) ON DELETE CASCADE;
16  
17 -- Add FK with a specific name
18 -- On Alter, if the column already exists but has no FK
19ALTER TABLE
20  tableName
21ADD CONSTRAINT fk_name
22  FOREIGN KEY (SomeEntityID) REFERENCES SomeEntityTable(ID) ON DELETE CASCADE;

1ALTER TABLE jobs DROP FOREIGN KEY constraint_name 

1SET foreign_key_checks = 0;

1CREATE TABLE parent (
2    id INT NOT NULL,
3    PRIMARY KEY (id)
4) ENGINE=INNODB;
5
6CREATE TABLE child (
7    id INT,
8    parent_id INT,
9    INDEX par_ind (parent_id),
10    FOREIGN KEY (parent_id)
11        REFERENCES parent(id)
12        ON DELETE CASCADE
13) ENGINE=INNODB;

1ALTER TABLE table_name DROP FOREIGN KEY constraint_name
2

1
2ALTER TABLE Orders
3
4DROP FOREIGN KEY FK_PersonOrder;