Diksha IT Training Centre

                             Normalization in Oracle database.     Hello Everyone , Today I am going to discuss about Normalization . Before starting this topic   I suggest you to please go through my previous blogs for your reference. Let’s discuss about Normalization. Normalization rules divide larger tables into smaller tables and links them using relationships. Normalization in Database is very important as it is the process of taking data from a problem and reducing it to a set of relations while ensuring data integrity and eliminating data redundancy.   In Simple word Normalization is a database design technique that reduces data redundancy and eliminates undesirable characteristics like Insertion, Update and Deletion . Below are the Key Points in Normalization. Data Integrity : All of the data in the database are consistent , and satisfy all integrity constraints. Data Redundancy : If   data in the database can be found in two different locations( Direct redundancy)

  Order By and Distinct Clause in Oracle.   Today I will discuss about SQL Order by and Distinct Clause which is vastly used in SQL query to perform Operation in query. I suggest you to please see my previous blog for your reference First start with Order By clause with Syntax and example. Order by Clause: ORDER BY clause is used to sort the records in the result set for a SELECT statement. Order by clause is used to sort the result-set in ascending or descending order. The Order By clause sorts the records in ascending order by default. To sort the records in descending order, use the DESC command in SQL. The Syntax of Order by Clause in SQL is as below: SELECT expression FROM table_name [WHERE conditions] ORDER BY expression [ ASC | DESC ];   In Above syntax : Expression: We need to specify the columns that will be retrieved or also we can use function for calculation to retrieve the column. Table_name : Table is object which stored in the database , we

    Logical Operator and other Operators uses in Oracle SQL.   Hello Everyone, Today I will discuss about Logical Operator used in Oracle SQL. This Topic is important as you can use Logical Operator in several SQL queries to get the result set as per your requirement.   I suggest you to please go through my previous blogs which you will able to see in archive folder so that you can use Logical Operator in SQL Queries. Let’s start with Logical Operators used in SQL. SQL operators are reserved keywords which basically used in the WHERE clause of a   SQL Statement to perform arithmetic, logical and comparison operations. Since, there are different types of operators in SQL, let us understand different type of operator and its uses in SQL. Below are the Logical Operators used in SQL . AND OR NOT BETWEEN LIKE IN EXIST ALL ANY     Uses of above operator in SQL 1.       AND Operator: AND operator displays the records, which satisfy all the condition separat

  Pseudo Column in Oracle. Hello Everyone, Today I will discuss about Pseudo column in Oracle. This topic is very important so before going to read this blog, I suggest you to please see my previous blogs which is in archive folder for your reference so that it’s easy for you to understand this topic. Let’s discuss about Pseudo Column in Oracle. Pseudo column: A pseudo-column is dynamic in Oracle as it behaves like a table column but is not stored in the table. Pseudo column behaves like a table column, but is not actually stored in the table. You can select from pseudo columns, but you cannot insert, update, or delete their values. A pseudo column is also similar to a function without arguments. In   Simple word we can say Pseudo column is a column that yields a value when selected, but which is not an actual column of the table. An example is RowID or SysDate. It can be use in combination with the DUAL table. Below are the Pseudo Column commonly used in Oracle Database:

                               Views and Types of View in Oracle.   Hello Everyone, In this blog I will discuss about Views and types of Views in Oracle Database .Views plays very important role in database as   Views are Virtual table that can be created from existing or base table. A view can be known as a ‘Stored Query’ or a “Virtual Table”. Views mainly used for security purpose and view used in most places where a table can be used. The table from which view is created are called based table. We can query view just like a table , but views doesn’t required disk space. A view representing a subset of the data present in a table, and performing functions such as joining and simplification of multiple tables into a single table, data aggregation, handling data complexity, providing security etc. A view can be created by SQL DDL create command i.e Create view statement View can be created from single base table or can be created from multiple tables by using joins, aggregate