Answers for "how to add foreign key in oracle sql"

SQL
25

mysql add foreign key

-- On Create
CREATE TABLE tableName (
    ID INT,
    SomeEntityID INT,
    PRIMARY KEY (ID),
    FOREIGN KEY (SomeEntityID)
        REFERENCES SomeEntityTable(ID)
        ON DELETE CASCADE
);

-- On Alter, if the column already exists but has no FK
ALTER TABLE
  tableName
ADD
  FOREIGN KEY (SomeEntityID) REFERENCES SomeEntityTable(ID) ON DELETE CASCADE;
  
 -- Add FK with a specific name
 -- On Alter, if the column already exists but has no FK
ALTER TABLE
  tableName
ADD CONSTRAINT fk_name
  FOREIGN KEY (SomeEntityID) REFERENCES SomeEntityTable(ID) ON DELETE CASCADE;
Posted by: Guest on April-27-2020
0

foreign key plsql

CREATE TABLE supplier
( supplier_id numeric(10) not null,
  supplier_name varchar2(50) not null,
  contact_name varchar2(50),
  CONSTRAINT supplier_pk PRIMARY KEY (supplier_id)
);

CREATE TABLE products
( product_id numeric(10) not null,
  supplier_id numeric(10) not null,
  CONSTRAINT fk_supplier
    FOREIGN KEY (supplier_id)
    REFERENCES supplier(supplier_id)
);
Posted by: Guest on April-01-2020
0

how to create table in oracle sql syntax example and foreign key

CREATE TABLE hr.admin_emp (
         empno      NUMBER(5) PRIMARY KEY,
         ename      VARCHAR2(15) NOT NULL,
         ssn        NUMBER(9) ENCRYPT,
         job        VARCHAR2(10),
         mgr        NUMBER(5),
         hiredate   DATE DEFAULT (sysdate),
         photo      BLOB,
         sal        NUMBER(7,2),
         hrly_rate  NUMBER(7,2) GENERATED ALWAYS AS (sal/2080),
         comm       NUMBER(7,2),
         deptno     NUMBER(3) NOT NULL
                     CONSTRAINT admin_dept_fkey REFERENCES hr.departments
                     (department_id))
Posted by: Guest on January-18-2021
4

foreign key on table oracle

SELECT c.OWNER, a.TABLE_NAME, a.COLUMN_NAME, a.CONSTRAINT_NAME, 
       c.R_OWNER AS REF_OWNER, cpk.TABLE_NAME AS REF_TABLE, 
       cpk.CONSTRAINT_NAME AS REF_PK
FROM ALL_CONS_COLUMNS a 
JOIN ALL_CONSTRAINTS c ON a.OWNER = c.OWNER
    AND a.CONSTRAINT_NAME = c.CONSTRAINT_NAME
 JOIN ALL_CONSTRAINTS cpk ON c.R_OWNER = cpk.OWNER
    AND c.R_CONSTRAINT_NAME = cpk.CONSTRAINT_NAME
WHERE c.CONSTRAINT_TYPE = 'R' AND c.TABLE_NAME= 'table_name';
Posted by: Guest on July-03-2021

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