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Monthly Archives: April 2013

SQL Query – Order of execution

April 29, 2013 2:36 pm / 1 Comment on SQL Query – Order of execution

Order of execution

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When you execute a SQL Query, it will be executed in the following sequence.

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SQL Syntax

April 8, 2013 1:35 pm / Leave a comment

SQL Syntax

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I hope you guys have gone through my previous tutorial SQL – A database language. Now let’s move little bit further to write basic SQL queries.

Since you guys are beginners in SQL, i am going to start with a basic SQL query syntax. Later we will go through lots of complex syntaxes.

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SQL – A database language

April 7, 2013 5:25 pm / Leave a comment

SQL

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SQL Stands for Structured Query Language.

It is a programming language to interact with databases. By executing SQL queries, we can Access, Insert, Update and Delete the data from databases. In earlier 1970’s, Donald D. Chamberlin and Raymond F. Boyce developed SQL at IBM.

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CODD Rules

April 7, 2013 9:33 am / Leave a comment

CODD Rules

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Edgar F. Codd, proposed thirteen rules (0 to 12) to define what is require d from a DBMS in order for it to be considered relational. Currently there is no commercial database management system which fully satisfies all the CODD’s rules.

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ACID Properties

April 4, 2013 7:56 pm / Leave a comment

ACID Properties

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The acronym ACID stands for Atomicity, Consistency, Isolation and Durability.

These are group of properties that every DBMS must satisfy. Any database is said to be reliable, if it meets all these properties. Otherwise, we consider that DBMS as not reliable.

 Let’s drown deep in ACID 🙂 🙂 🙂

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The Table family

April 4, 2013 6:18 am / 1 Comment on The Table family

A Database table

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 A table is a basic unit of data storage in database which organizes the data in rows(Tuples) and columns(Attributes/fields). Each row in a table contains one record and it simply refers to a two dimensional representation of your data using rows and columns. A table has a specified number of columns, but can have any number of rows. In short, a table is the only thing for storing data in the database.

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