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                Set Operator uses and Benefits in Oracle Database   Today we will discuss about different Set operators used in SQL with examples. SET operator used to select data from multiple tables as Set operators combine the results of two component queries into a single result. Queries containing set operators are called compound queries. Through SET Operator in SQL we don’t need to use Joins and make alias of table to get the common record and all distinct row selected by query. SQL Set Operators are of 4 parts which work similar to Mathematics which we learn in class 10 th  or so. 1.     UNION 2.     UNION ALL 3.     INTERSECT 4.     MINUS/EXCEPT.     Things to Remember while using SET operator: Select clause should have the same number of columns and columns must be of same data type, Column needs to ...

  Data Dictionary and its importance in Oracle Database.   Today I will discuss about Data Dictionary table in Oracle Database. Data Dictionary table provide information needed by those who build systems and applications that support the data. If you know the data dictionary table names you can able to see the objects present in the database as well as also you can able to see the design , relations etc by using Data Dictionary table. Let understand about Data Dictionary first. Data Dictionary: Most important parts of an Oracle database is its data dictionary, which is a read only set of tables that provides information about the database. In Oracle database data dictionary provide useful information about the database including schema, users, privileges etc. The values in these stored dictionaries are updated automatically by Oracle anytime a statement is executed on the server that modifies the data. Note: Read-only data dictionaries can be read and queried just...

  Package in Oracle and it’s Advantage in PL/SQL Program. Hello Everyone, In my Previous Blogs I Discussed about Stored Procedures, Stored Functions, Cursor etc. Today we will discuss about Oracle Packages. Oracle Package plays very important role in PL/SQL program . Package we can say collection of Procedures , Functions , Cursor etc . In another word we can say A package is a schema object that groups logically related PL/SQL types, variables, and subprograms.   Packages usually have two parts: Package Specification and Package Body, Sometimes the body is not required .The specification is the main interface to the package. It declares the types, variables, constants, exceptions, cursors, and subprograms that can be referenced from outside the package. The body mainly defines the queries for the cursors and the code for the subprograms. PL/SQL Package is very important in Database and as mentioned above it contains multiple procedures , Functions, variables , cur...

                Stored Function in Oracle Database and it’s benefit. Hello Everyone, In my previous blogs we discussed about stored procedures and its attributes and benefits of using Stored Procedure in Databases. Today we will discuss about Stored Function. Stored Function is also named block like Stored Procedure a stored function is a set of PL/SQL statements you can call by name. Stored functions are very similar to procedures, except that a function returns a value. Stored functions must return a value whether condition is true or false, but in Stored procedure value should return only when condition is true.   Stored function only return one value, whereas in stored procedure if condition is true it can give you multiple record as well as multiple transaction. Stored Function can be used in Procedures, Packages as well as into select statement, but procedure can’t be called in select statement. Both Stored Procedures and functions ...