Technical Development - Tiveloper.

Simple Views and Complex Views A simple view Derives data from only one table No functions or groups DML operations through the view A complex view more than one table contains functions and groups DML operation might be limited CREATE [OR REPLACE] [FORCE | NOFORCE] VIEW view_name [(alias[, alias] ... )] AS subquery [WITH CHECK OPTION [CONSTRAINT constraint]] [WITH READ ONLY [CONSTRAINT constrai..

Simple Views and Complex Views A simple view Derives data from only one table No functions or groups DML operations through the view A complex view more than one table contains functions and groups DML operation might be limited CREATE [OR REPLACE] [FORCE | NOFORCE] VIEW view_name [(alias[, alias] ... )] AS subquery [WITH CHECK OPTION [CONSTRAINT constraint]] [WITH READ ONLY [CONSTRAINT constrai..

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