Downloaded 2,597 times
Uploaded byEhsan Hamzei
Introduction to SQL
This document provides an introduction to SQL and relational database concepts. It explains that SQL is used to manipulate and retrieve data from relational databases. It also outlines the main SQL commands: DDL for data definition, DML for data manipulation, DCL for data control, and DQL for data queries. Key relational database concepts like tables, records, columns, and relationships are defined. Constraints, data types and integrity are discussed. Examples are provided for SQL statements like CREATE, INSERT, UPDATE, DELETE, and SELECT.
More Related Content
Similar to Introduction to SQL
Introduction to SQL
- 1. Introduction to SQL UNIVERSITY OFTEHRAN NOVEMBER, 2016
- 2. What is SQL? Structured Query Language SQL is Structured Query Language, which is a computer language for storing, manipulating and retrieving data stored in relational database. SQL is the standard language for Relation Database System. All relational database management systems like “MySQL, MS Access, Oracle, Sybase, Informix, postgres and SQL Server” use SQL as standard database language.
- 3. SQL Commands DDL- Data Definition Language DML - Data Manipulation Language DCL - Data Control Language DQL - Data Query Language
- 4.
- 5.
- 6. SQL RDBMS Concepts TABLE RECORD COLUMN CELL NULL?
- 7. SQL RDBMS Concepts SQL Constraints: (applied on columns) NOT NULL Constraint UNIQUE Constraint PRIMARY Key FOREIGN Key CHECK Constraint Data Integrity: Entity Integrity: There are no duplicate rows in a table Domain Integrity: Enforces valid entries for a given column by restricting the type Referential Integrity: Rows cannot be deleted which are used by other records User-Defined Integrity: Enforces some specific business rules
- 8. SQL RDBMS Concepts Data Types: Character datatypes: CHAR NCHAR NVARCHAR2 VARCHAR2 Numeric datatypes: NUMBER BINARY_FLOAT BINARY_DOUBLE Date time datatype: DATE
- 9. DCL: CREATE USER 1) Define User with Username/Password 2) Grants Sufficient Privileges. Using SQL Developer (UI, Command) Using SQL *PLUS (Command)
- 10. SQL : DDL Create Table: COLUMNS CONSTRAINTS
- 11. SQL: DDL DROPTABLE: ALTER TABLE OTHER DDL COMMANDS!!!!
- 12. SQL: DML: INSERT INSERT INTO: NUMBER, CHAR/VARCHAR2, DATE?
- 13. SQL: DML: INSERT INSERT INTO: SPECIFIC COLUMNS
- 14. SQL: DML: INSERT INSERT INTO: FOREIGN KEY ALL DML COMMANDS NEED COMMIT
- 15. SQL: DML: UPDATE UPDATE WHERE CLAUSE
- 16. SQL: DML: DELETE DELETE (DELETE VS DROP????)
- 17.
- 18. SQL: DQL: SELECT SELECT * SPECIFIC COLUMNS
- 19. SQL: DQL: SELECT DISTINCT CLUASE
- 20. SQL: DQL: SELECT WHERE CLUASE
- 21. SQL: DQL: SELECT IN CLUASE NOT IN NULL IN WHERE? IS NULL IS NOT NULL
- 22. SQL: DQL: SELECT ORDER BY
- 23. SQL: DQL: SELECT GROUP BY AGGREGATE FUCTION MAX,MIN AVG COUNT SUM … HAVING CLAUSE
- 24. SQL: DQL: SELECT SELECT FROM MULTIPLE TABLES CARTESIAN MULTIPICATION JOIN
- 25. About Me EhsanHamzei Graduate Student of Geospatial Information System University of Tehran Git-Hub: https://github.com/ehsan-hamzei/ Source-Codes: https://github.com/ehsan- hamzei/Oracle-SQL/
Editor's Notes
- #21 کارمندانی که حرف o در اسمشون هست و در سال 2003 به بعد استخدام شده اند. SELECT * FROM EMPLOYEES WHERE FIRST_NAME LIKE '%o%' AND HIRE_DATE >= TO_DATE('01-JAN-2003');