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All data and structure in the table are deleted.Any pending transactions are committed.All indexes and constraints are dropped.Roll back is impossible.DROP TABLE tablename; ** The Oracle server doesn't question the action when you issue the DROP TABLE statement. ** Auto commit.

All data and structure in the table are deleted.Any pending transactions are committed.All indexes and constraints are dropped.Roll back is impossible.DROP TABLE tablename; ** The Oracle server doesn't question the action when you issue the DROP TABLE statement. ** Auto commit.

Creates a Table and Inserts Rows CREATE TABLE table [(column, column , ...0 ] AS subquery - Match the number of specified columns to the number of subquery columns. - Define columns with column names and default values. 1. The table is creted with the specified column names, and the rows retrieved by the SELECT statement are inserted into the table. 2. The column definition can contain only the ..

Creates a Table and Inserts Rows CREATE TABLE table [(column, column , ...0 ] AS subquery - Match the number of specified columns to the number of subquery columns. - Define columns with column names and default values. 1. The table is creted with the specified column names, and the rows retrieved by the SELECT statement are inserted into the table. 2. The column definition can contain only the ..

UPDATE employees SET department_id = 55 WHERE department_id = 110; UPDATE employees * ERROR at line 1:ORA-02291: integrity constraint (HR.EMP_DEPT_FK) violated - parent key not found Department 55 doesn't exist in the parent table. You cannot delete a row that contains a primary key that is used as a foreign key in another table. DELETE FROM departments WHERE department_id = 60; DELETE FROM depa..

UPDATE employees SET department_id = 55 WHERE department_id = 110; UPDATE employees * ERROR at line 1:ORA-02291: integrity constraint (HR.EMP_DEPT_FK) violated - parent key not found Department 55 doesn't exist in the parent table. You cannot delete a row that contains a primary key that is used as a foreign key in another table. DELETE FROM departments WHERE department_id = 60; DELETE FROM depa..

1. Defines a condition 2. Not-Allowed expressions : - CURRVAL, NEXTVAL, LEVEL, ROWNUM pseudocolumns - SYSDATE, UID, USER, and USERENV functions - Queries that refer to other values in other rows ex) .... , salary NUMBER(2) CONSTRAINT emp_salary_min CHECK (salary > 0 ), ..... 3. A single column can have multiple CHECK constraints

1. Defines a condition 2. Not-Allowed expressions : - CURRVAL, NEXTVAL, LEVEL, ROWNUM pseudocolumns - SYSDATE, UID, USER, and USERENV functions - Queries that refer to other values in other rows ex) .... , salary NUMBER(2) CONSTRAINT emp_salary_min CHECK (salary > 0 ), ..... 3. A single column can have multiple CHECK constraints

1. A foreign key value must match an existing value in the parent table or be NULL 2. Foreign keys are based on data values and are purely logical, rather than physical, pointer. CREATE TABLE employees ( employee_id NUMBER(6) , first_name VARCHAR2(20) , last_name VARCHAR2(25) NOT NULL , email VARCHAR2(25) , phone_number VARCHAR2(20) , hire_date DATE ..... ,department_id NUMBER(4) ,CONSTRAINT emp..

1. A foreign key value must match an existing value in the parent table or be NULL 2. Foreign keys are based on data values and are purely logical, rather than physical, pointer. CREATE TABLE employees ( employee_id NUMBER(6) , first_name VARCHAR2(20) , last_name VARCHAR2(25) NOT NULL , email VARCHAR2(25) , phone_number VARCHAR2(20) , hire_date DATE ..... ,department_id NUMBER(4) ,CONSTRAINT emp..