ORA-02291: integrity constraint violated – parent key not found error occurs when we try to insert a row in a child table with a foreign key constraint and the related… Read more »
Foreign Key holds the reference to another table column value.It is also known as references constraint.
A foreign key means that values in one table must also appear in another table.
Composite primary key is a special type of primary key comprises a set of columns.In relational database a primary key is a candidate key to uniquely identify each row in a table.
CREATE TABLE AS SELECT statement can be used when we need to extract part or full data from a table and store it into another table based on certain conditions
Usage Create table statement with foreign key constraint will create table with referential integrity
Foreign Key holds the reference to another table column value.It is also known as references constraint
CREATE TABLE statement: create a table with composite primary key.
Oracle PL/SQL:CREATE TABLE statement: create a table with primary key.
CREATE TABLE statement is used to create table objects in database.You can create tables with different column data types.It is possible to add CONSTRAINTS like primary key ,foreign key etc while creating the table or can be added after the table creation
Primary key is a type of constraint used in Oracle tables.A primary key is used to uniquely identify each row in a table.A primary key can consist of one or more fields on a table. When more than one fields are used as a primary key, the key is called a composite key.