July 7, 2020
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  • 11:09 am PHIM MỚI 2020 | TẠI SAO BOSS MUỐN CƯỚI TÔI – TẬP 1 | PHIM TÌNH CẢM HAY NHẤT 2020
  • 11:06 am "IS IT ME OR DOES THIS GAME SHOW A LOT OF CLEAVAGE?" – [Street Fighter 5 STORY#5]
  • 11:04 am Cách chọn chó Bắc Hà chuẩn đét 100% – Part 1
  • 10:44 am Học Bách Khoa có khó không ? | Hỏi nhanh đáp gọn



A relational database management system (RDBMS) is a database management system (DBMS) that is based on the relational model as invented by E. F. Codd, of IBM’s San Jose Research Laboratory. Many popular databases currently in use are based on the relational database model.RDBMSs have become a predominant choice for the storage of information in new databases used for financial records, manufacturing and logistical information, personnel data, and much more since the 1980s. Relational databases have often replaced legacy hierarchical databases and network databases because they are easier to understand and use. However, relational databases have been challenged by object databases, which were introduced in an attempt to address the object-relational impedance mismatch in relational database, and XML databases.

Object-relational database management system (ORDBMS)
============================================
An object-relational database can be said to provide a middle ground between relational databases and object-oriented databases (OODBMS). In object-relational databases, the approach is essentially that of relational databases: the data resides in the database and is manipulated collectively with queries in a query language; at the other extreme are OODBMSes in which the database is essentially a persistent object store for software written in an object-oriented programming language, with a programming API for storing and retrieving objects, and little or no specific support for querying.

Object-relational database management systems grew out of research that occurred in the early 1990s. That research extended existing relational database concepts by adding object concepts. The researchers aimed to retain a declarative query-language based on predicate calculus as a central component of the architecture. Probably the most notable research project, Postgres (UC Berkeley), spawned two products tracing their lineage to that research: Illustra and PostgreSQL.

Many of the ideas of early object-relational database efforts have largely become incorporated into SQL:1999 via structured types. In fact, any product that adheres to the object-oriented aspects of SQL:1999 could be described as an object-relational database management product. For example, IBM’s DB2, Oracle database, and Microsoft SQL Server, make claims to support this technology and do so with varying degrees of success.

SQL(Structures Query Language)
========================
SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce in the early 1970s. This version, initially called SEQUEL (Structured English Query Language), was designed to manipulate and retrieve data stored in IBM’s original quasi-relational database management system, System R, which a group at IBM San Jose Research Laboratory had developed during the 1970s.The acronym SEQUEL was later changed to SQL because “SEQUEL” was a trademark of the UK-based Hawker Siddeley aircraft company.

SQL*Plus
=======
SQL*Plus is a command line SQL and PL/SQL language interface and reporting tool that ships with the Oracle Database Client and Server software. It can be used interactively or driven from scripts. SQL*Plus is frequently used by DBAs and Developers to interact with the Oracle database.
If you are familiar with other databases, sqlplus is equivalent to:
“sql” in Ingres,
“isql” in Sybase and SQL Server,
“sqlcmd” in Microsoft SQL Server,
“db2” in IBM DB2,
“psql” in PostgreSQL, and
“mysql” in MySQL.

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16 COMMENTS

  1. Izhar Ali Posted on July 7, 2020 at 10:07 am

    please share the setup

    Reply
  2. Munir Ahmed Posted on July 7, 2020 at 10:07 am

    If you use set pagesize 20 that will show complete table. Your table shows a breakup. Just if you can use it.

    Reply
  3. Tusarkanta Mohapatra Posted on July 7, 2020 at 10:07 am

    how to download oracle 9i .
    please help me

    Reply
  4. fatima sayed Posted on July 7, 2020 at 10:07 am

    How to download this software from internet

    Reply
  5. wurngarin awungshi Posted on July 7, 2020 at 10:07 am

    I want to shit

    Reply
  6. NAND KUMAR SAHU Posted on July 7, 2020 at 10:07 am

    repeating same command again and again.. ha ha

    Reply
  7. Ashutosh Kamble Posted on July 7, 2020 at 10:07 am

    Sir start A create table employees Land and Erica nd queries also plzzzz

    Reply
  8. RAJESH K GUPTA Posted on July 7, 2020 at 10:07 am

    your voice look like hrithik'

    Reply
  9. padma makireddy's Posted on July 7, 2020 at 10:07 am

    nice tutorial sir,thanks a lot.

    Reply
  10. Santhosh Raghul Posted on July 7, 2020 at 10:07 am

    scott and tiger not working. I installed oracle 9i just now and don't know the username and password for SQL plus

    Reply
  11. Harish hari 53 Posted on July 7, 2020 at 10:07 am

    dude from where did u download Sql plus??

    Reply
  12. Salman Kamran Posted on July 7, 2020 at 10:07 am

    Please tell me the best book of sql in which all the examples are related to only emp table.I need an introductory level book.

    Reply
  13. Android Son Posted on July 7, 2020 at 10:07 am

    https://play.google.com/store/apps/details?id=atabase.complex
    Learn SQL with your Android mobile device! Free at play.google.com

    Reply
  14. aps miransahib jmu Posted on July 7, 2020 at 10:07 am

    nyce

    Reply
  15. William Alvarez V Posted on July 7, 2020 at 10:07 am

    thank you for this video. i´m from colombia, so please excuse me writing, so i want export some tables and their content from a database in oracle 9i to a new schema in oracle 11g r2, can you help me, wiht some explanation,
    again thank you very much

    Reply
  16. Venkat Swamy Posted on July 7, 2020 at 10:07 am

    good lecture and very helpful to students.

    Reply
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