Introduction to SQL: Querying and managing data
Introduction to SQL | SQL is a standard query language, which is used to the community with DB. SQL statements are used to perform tasks like defining, updating & retrieving data from DB. Some RDBMS that used SQL are:
Ms. SQL Server: T-SQL
Oracle is a leading RDBMS developed by oracle corporation. Provides interface tools to access data stored in oracle DB. The major tools are :
- SQL*PLUS – Which is a command-line interface (CLI).
- SQL Developer:- A collection of firms, reports and GUI
- Oracle forms:- It is a GUI based tool used to develop data entry forms and menus that access tables in an oracle DB.
- Oracle Report:– It is a GUI based tool used to develop reports that access tables in oracle DB.
- Oracle Jdeveloper:- It is a general-purpose java integrated development environment. which is pre-loaded with classes and methods used to connect and manipulate schema in oracle DB.
Oracle SQL *PLUS is an interactive command-line tool that allows a user to type SQL statements to be executed directly on the oracle database. It has an ability to format database output, save frequently used comments, and can be invoked from other oracle tools.
SQL *PLUS commands:-
SQL *PLUS commands allow the user to manipulate and submit SQL statements specifically they enable a user to:
- Enter, Edit, Store, Retrieve, and Run SQL Statements.
- List the columns definition for any table.
- Format, Perform calculations, store, and print query results in the form of the report.
Some frequently used SQL *PLUS commands are :
PL/SQL:- SQL language used in SQL *PLUS is PL/SQL. It is a proprietary Procedural Language. PL/SQL used as a query language to communicate with oracle DB.
importance of database backup and recovery