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                                                   SQL 
        About the Tutorial 
        SQL is a database computer language designed for the retrieval and management of data 
        in a relational database. SQL stands for Structured Query Language. 
        This tutorial will give you a quick start to SQL. It covers most of the topics required for a 
        basic understanding of SQL and to get a feel of how it works.   
         
        Audience 
        This tutorial is prepared for beginners to help them understand the basic as well as the 
        advanced  concepts  related  to  SQL  languages.  This  tutorial  will  give  you  enough 
        understanding on the various components of SQL along with suitable examples. 
         
        Prerequisites 
        Before you start practicing with various types of examples given in this tutorial, I am 
        assuming that you are already aware about what a database is, especially the RDBMS and 
        what is a computer programming language. 
         
        Compile/Execute SQL Programs 
        If you are willing to compile and execute SQL programs with Oracle 11g RDBMS but you 
        don’t have a setup for the same, do not worry. Coding Ground is available on a high-end 
        dedicated server giving you real programming experience. It is free and is available online 
        for everyone. 
         
        Copyright & Disclaimer 
         Copyright 2018 by Tutorials Point (I) Pvt. Ltd.  
        All the content and graphics published in this e-book are the property of Tutorials Point (I) 
        Pvt. Ltd.  The user of this e-book is prohibited to reuse, retain, copy, distribute or republish 
        any contents or a part of contents of this e-book in any manner without written consent 
        of the publisher.   
        We strive to update the contents of our website and tutorials as timely and as precisely as 
        possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. 
        Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our 
        website or its contents including this tutorial. If you discover any errors on our website or 
        in this tutorial, please notify us at contact@tutorialspoint.com 
         
         
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                                                                                                                                                     SQL 
                      Table of Contents 
                           About the Tutorial ............................................................................................................................................ i 
                           Audience ........................................................................................................................................................... i 
                           Prerequisites ..................................................................................................................................................... i 
                           Compile/Execute SQL Programs ....................................................................................................................... i 
                           Copyright & Disclaimer ..................................................................................................................................... i 
                           Table of Contents ............................................................................................................................................ ii 
                      1.   SQL ─ Overview ......................................................................................................................................... 1 
                           What is SQL? .................................................................................................................................................... 1 
                           SQL Process ..................................................................................................................................................... 2 
                           SQL Commands ................................................................................................................................................ 3 
                      2.   SQL ─ RDBMS Concepts ............................................................................................................................. 5 
                           What is RDBMS? .............................................................................................................................................. 5 
                           SQL Constraints ............................................................................................................................................... 6 
                           Data Integrity ................................................................................................................................................... 7 
                           Database Normalization .................................................................................................................................. 7 
                           Database – First Normal Form (1NF) ............................................................................................................... 8 
                           Database – Second Normal Form (2NF) ........................................................................................................ 10 
                           Database – Third Normal Form (3NF) ............................................................................................................ 11 
                      3.   SQL ─ RDBMS Databases ......................................................................................................................... 14 
                           MySQL ........................................................................................................................................................... 14 
                           MS SQL Server ............................................................................................................................................... 15 
                           ORACLE .......................................................................................................................................................... 16 
                           MS ACCESS ..................................................................................................................................................... 17 
                      4.   SQL – Syntax ........................................................................................................................................... 19 
                           Various Syntax in SQL .................................................................................................................................... 19 
                      5.   SQL ─ Data Types .................................................................................................................................... 24 
                      6.   SQL – Operators ...................................................................................................................................... 28 
                           What is an Operator in SQL? ......................................................................................................................... 28 
                           SQL Arithmetic Operators ............................................................................................................................. 28 
                           Arithmetic Operators – Examples ................................................................................................................. 29 
                           SQL Comparison Operators ........................................................................................................................... 30 
                           Comparison Operators – Examples ............................................................................................................... 31 
                           SQL Logical Operators ................................................................................................................................... 34 
                           Logical Operators – Examples........................................................................................................................ 35 
                      7.   SQL – Expressions ................................................................................................................................... 41 
                           Boolean Expressions ...................................................................................................................................... 41 
                           Numeric Expressions ..................................................................................................................................... 42 
                           Date Expressions ........................................................................................................................................... 43 
                      8.   SQL – CREATE Database .......................................................................................................................... 45 
                      9.   SQL ─ DROP or DELETE Database ............................................................................................................. 46 
                      10.  SQL ─ SELECT Database, USE Statement .................................................................................................. 47 
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                                                   SQL 
        11.  SQL ─ CREATE Table ................................................................................................................................ 48 
          SQL - Creating a Table from an Existing Table ............................................................................................... 49 
        12.  SQL ─ DROP or DELETE Table ................................................................................................................... 51 
        13.  SQL ─ INSERT Query ................................................................................................................................ 53 
        14.  SQL ─ SELECT Query ................................................................................................................................ 56 
        15.  SQL ─ WHERE Clause ............................................................................................................................... 59 
        16.  SQL ─ AND & OR Conjunctive Operators ................................................................................................. 62 
          The AND Operator ......................................................................................................................................... 62 
          The OR Operator ........................................................................................................................................... 63 
        17.  SQL ─ UPDATE Query .............................................................................................................................. 66 
        18.  SQL ─ DELETE Query ................................................................................................................................ 69 
        19.  SQL ─ LIKE Clause .................................................................................................................................... 72 
        20.  SQL ─ TOP, LIMIT or ROWNUM Clause .................................................................................................... 76 
        21.  SQL ─ ORDER BY Clause ........................................................................................................................... 79 
        22.  SQL ─ Group By ....................................................................................................................................... 82 
        23.  SQL ─ Distinct Keyword ........................................................................................................................... 86 
        24.  SQL ─ SORTING Results ........................................................................................................................... 89 
        25.  SQL ─ Constraints .................................................................................................................................... 92 
          SQL - NOT NULL Constraint ........................................................................................................................... 92 
          SQL - DEFAULT Constraint ............................................................................................................................. 93 
          SQL - UNIQUE Constraint ............................................................................................................................... 94 
          SQL ─ Primary Key.......................................................................................................................................... 95 
          SQL ─ Foreign Key .......................................................................................................................................... 96 
          SQL ─ CHECK Constraint ................................................................................................................................ 98 
          SQL ─ INDEX Constraint ................................................................................................................................. 99 
          Dropping Constraints ................................................................................................................................... 101 
          Integrity Constraints .................................................................................................................................... 101 
        26.  SQL ─ Using Joins .................................................................................................................................. 102 
          SQL - INNER JOIN ......................................................................................................................................... 103 
          SQL ─ LEFT JOIN ........................................................................................................................................... 105 
          SQL - RIGHT JOIN ......................................................................................................................................... 107 
          SQL ─ FULL JOIN ........................................................................................................................................... 109 
          SQL ─ SELF JOIN ........................................................................................................................................... 111 
          SQL ─ CARTESIAN or CROSS JOIN ................................................................................................................. 113 
        27.  SQL ─ UNIONS CLAUSE .......................................................................................................................... 116 
          The UNION ALL Clause ................................................................................................................................. 119 
          SQL ─ INTERSECT Clause .............................................................................................................................. 121 
          SQL ─ EXCEPT Clause ................................................................................................................................... 123 
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