SQL Archive
Foreign Keys Made Simple with MySQL by examples
SQL
Nov 16, 2013
In plain English : A FOREIGN KEY in one table points to a PRIMARY KEY in another table. A foreign key places constraints on data in the related tables to ensure and guarantee data referential integrity as well as consistency. Foreign Key Syntax: create table abc( abc_id int not null ..... ...
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SQL SELECT Tutorial for Nested Queries ( Sub Queries )
SQL
Nov 11, 2013
A Subquery or Inner query or Nested query is a query within another SQL query and embedded within the WHERE clause. A subquery is used to return data that will be used in the main query as a condition to further restrict the data to be retrieved. Subqueries can be used with
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SQL tutorial for using Having with Examples
The HAVING statment is added to SQL because the WHERE keyword could not be used with aggregate functions ( such as count, max …) [info] Advanced SQL SELECT Tutorial using Aggegrate Functions by Examples [/info] The syntax for using HAVING is as below: SELECT column_name, aggregate_function(column_name) FROM table_name WHERE column_name operator
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Advanced SQL SELECT Tutorial using Aggegrate Functions by Examples
[info]In case you are beginner with SQL, you are advised to visit the following tutorials: >SQL SELECT Tutorial : Searching & Querying the database >Join : SELECT Tutorial using multiple database tables[/info] The important SQL command is SELECT statement. The SQL SELECT statement is used to query or retrieve data from a
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Database Porgramming : Creating a simple phone book using Java & a database ( HSQLDB )
Databases, Java Programming, SQL
Apr 23, 2013
[info] You to have Java and Eclipse Configured and Installed. If not please install the JDK and download Eclipse[/info] In one of the last tutorial, we have created a simple phonebook system using a text file and Java Programming. For more details, click here. In this tutorial, we will be creating the
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Java & HSQLDB : Connecting to a DBMS (HSQLDB) from Java Program
Databases, Java Programming, SQL
Apr 17, 2013
[info]In case you don’t have the HSGLDB, You can download the DBMS : HSQLDB from here [/info] 1) Create a simple file and call it Simple.java. Here is a simple code written in Java to connect to a DBMS : import java.io.*; import java.sql.*; import java.util.*; public class Simple { public static
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Join : SELECT Tutorial using multiple database tables
The JOIN is used in an SQL statement to query data from two or more tables, based on a relationship between certain columns in these tables. Tables in a database are often related to each other with keys. [info] In case you are not familiar with SELECT, visit this tutorial : SQL
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SQL SELECT Tutorial : Searching & Querying the database
The most commonly used SQL command is SELECT statement. The SQL SELECT statement is used to query or retrieve data from a table in the database. A query may retrieve information from specified columns or from all of the columns in the table. To create a simple SQL SELECT Statement, you must
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SQL Tutorial : Creating a Table and Inserting data ( MySQL & HSQLDB )
In this tutorial, we will learn how to create a database table and insert data into it, The example we will consider is a simple phone book to store names, last names, ages, email and phone numbers for people. What is SQL? SQL stands for Structured Query Language SQL lets you
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SQL Hello World: A simple guide to database systems using HSQLDB
In this tutorial, we will learn how to create a simple database and play with its content. The example we will consider is a simple phone book to store names, last names and phone numbers for people. 1) We need to download the DBMS ( HSQLDB ): [a software that eases and
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