DB Desk

  Some of my friend ask me about there are some restrictions on accessing other features of DBMS on end users because he worked in an organization where all the features are not get accessed. Every user in the database has a role which is defined by the Database Administrator. Users use features according to there needs, many features are restricted due to insufficient privileges because special permissions are needed. Benefits of Database Privileges Normal user can’t delete your tables of harm your database. No extra queries will deployed save traffic and load. Nobody can seen the private data Except special peoples. Maintenance of database can easily be handle. Easy to access recent data and rollback. Attacks and brute force attacks saved. Easily banning and get back the privileges from Database Administrator.

  Data Consistency: Definition 1: Data consistency means that the changes made to the different occurrences of data should be controlled and managed in such a way that all the occurrences have the same value for any specific data item. Data inconsistency leads to a number of problems, including loss of information and incorrect results. In the database approach, it is controlled because data is shared and consistency is controlled and maintained. Data Consistency Definition 2: Data consistency meaning is the validity, accuracy and usability of related data. It ensures that each user observes a consistent(Same) view of the data, including changes made by the user’s own transactions and transactions of other users. Types of Data Consistency: Point in time consistency Transaction consistency Application consistency Data Inconsistncy: Data Inconsistency Definition: Data inconsistency meaning is that different versions of the same data appear in diffe

  What is Software Testing? The software testing phase starts when you have done the coding and designing phase of the software. A developer first priority (after coding) is software testing to find the bugs. Testing is lifted to identify either all phases completed and to ensure the working, stability and quality of the software going to be delivered. Number of testing activities incorporated to find the possibility of any error or bugs to make it more reliable and bug free before releasing the software. Why software Testing is important? Software testing is to ensure the features of the software is gathered and completed. We have listed some of the software testing aspect why it is important. The software is according to the expectation of the client. The deliverable software is in working condition. software is client/user friendly. Software Development/Coding: Software development is actually the coding phase of the computer programming which is to build fun

  Now a days almost all applications are based on OOP (object oriented programming); and use case diagrams depicts the functionality to be implemented in a system. On the other hand DFD (Data Flow Diagram) is the true depiction of OOP based programming.   Use Case & Data Flow Diagram are same? Use case diagrams and DFD are not contradicting each other as far as system architecture is concerned. DFD diagram and Use case diagram are used to view the system from different perspective/angle. A graphical representation of the flow of data or information in a system or part of system. It consists of data flows, processes, sources, destinations and stores. Difference Between Use Case & Data Flow Diagram A DFD(Data Flow Diagram) only shows the sources and destinations of data coming and going from the system and the transformation of data when it passes through some system process. A Use Case is used to capture the functional requirements of the system. A use case i

  What the difference between Flow charts and Flow Graph? why can't we utilize Flow charts for software testing? A program's flow charts resembles a control flow graph but there are some differences which are provided below: Difference: Flow Charts and Flow Graph 1. In flow graphs, we don't show the details of what is in a process block whereas in flow charts every part of the process block is drawn. 2. In flow charts, different types of nodes are represented by different symbols, but we do not use different symbols in control flow graphs. 3. The flow graph focuses on control flow of the program whereas the flowchart focuses on process steps and due to this reason, flow charts are not used for testing. What is Flow Charts  Graphic representation or Symbolic representation of process shown in the figure below called Flow charts. So different symbols are used to denote process which contains a little description of the process. These symbols are linked t

  Deadlock Definition 1: A deadlock occurs when the first transaction has locks on the resources that the second transaction wants to modify, and the second transaction has locks on the resources that the first transaction intends to modify. Definition 2: Deadlock is a condition where multiple processes are blocked by one another because one process is holding a resource and waiting for another resource acquired by some other process. consider the diagram Process 1 waiting for process 2, and process 2 is waiting for process 3 thus all are in circular wait which cause deadlock. Example of Dead Lock Deadlock Example 1: Consider, when two buses moving toward each other on same track and here is only 1 track, none of the bus because they are in-front of each other. Similar condition occurs in operating systems when there are two or more processes hold some resources and wait for resources held by other(s).  For example, in the below diagram, Process 1 is holdi

  Three Level Database Architecture The Three level database architecture, also known as the three level of Abstraction which is concerned to schema. The word Schema means structure , either any website like (Amazon or flip-kart) stores the data in any format and they have defined a structure. Three schema means With respect to the ANSI/SPARC three level database architecture in dbms is defined as follows. What is Schema: Example: We have data roll no, name, marks we are going to store that data in table.  In this condition our schema or structure in the form of Table . External Level of Database Architecture: External level, view or schema is used to store the definitions of different views in order to support different user groups. Those views are provide data help from database how it is flowing. Then a programmer make program according to them. Conceptual Level of Database Architecture: Conceptual level, view or schema is used to store the structure of whole datab

  Logical Relationship in Tables: Database tables have a major advantage to bridge them with some logical relationship so to filter the records. These relationship allowed us to access one table data using another table records(via columns or rows). In other words logical filtration is called cardinality DBMS. Read Also: Relational Model in DBMS Definitions of Cardinality in DBMS: Definition 1: A number that represents, one instance of first entity(table) is related to how many instances of the second entity, is known as cardinality in dbms. Definition 2: Cardinality is a relationship or join/bridge between rows of  1 table to the rows of another table. via some column (e.g. User Table column {user_id} in another table Posts to filter the posts by user_id). Types of Cardinality in DBMS: There are three types of Cardinality in DBMS. one-to-one one-to-many many-to-one many-to-many Read Also: Degree of Relationship in DBMS one-to-one

 There are 3 types of commands in SQL database , DDL commands, DML commands and TCL commands means transactions control language. While transactions in SQL are queries you run to perform a task. the commands of transactions control includes commit, rollback and savepoints. What is Transaction in SQL: A set of SQL queries which are use to perform a well defined tasks.or When we run multiple queries or bunch of queries in single run is called transactions in SQL. For example you are working on library management system or maintaining a database for library. You are about to issue a book to the reader, the criteria would be perform. You have to reduce a copy of book from the table. The member table whom you issue the book must be updated. How many book have been issue to particular member. We have to update on which date, which member a book issued. All above 4 will be performed separately via SQL query and become a transaction of queries. Transaction Commands of SQL: Co

A logic gates are basic block for digital circuits. Most of the logic gates consists of 2 inputs and one output. While in operation a logic gate terminal/point is in two binary conditions low (0) or high (1),  having different voltage levels. When a circuit starts processing data the terminal change it's state and change often. Most of the logic gates approximately have 0 volts (0 V), while the high state is approximately five volts positive (+5 V).   There are seven basic logic gates: AND, OR, XOR, NOT, NAND, NOR, and XNOR.   AND GATE:   The AND gate is so named because, if 0 is called "false" and 1 is called "true," the gate acts in the same way as the logical "and" operator. The following illustration and table show the circuit symbol and logic combinations for an AND gate. (In the symbol, the input terminals are at left and the output terminal is at right.) The output is "true" when both inputs are "true." Otherwise, t

  Foreach is a loop and support by numbers of language in different manner. Their syntax and usage are different but some how they work same in the manner that everybody can work with it.Languages includes PHP, C#, C++, JavaScript, jQuery,  Oracle. We have demonstrated some of the examples from different web pages which includes many sites. But lets look at different language foreach loop syntax and how to use it. Foreach Loop in Different Languages  PHP <?php $colors = array("red", "green", "blue", "yellow"); foreach ($colors as $value) {     echo "$value <br>"; } ?> C# // You can maintain a count of the elements in the collection.         int count = 0;         foreach (int element in fibarray)         {             count += 1;             System.Console.WriteLine("Element #{0}: {1}", count, element);         } JavaScript var sum = 0; var obj = {prop1: 5, prop2: 13, prop3: 8}; fo

 How do represent an multi-valued attribute in E-R diagram? How can we transfer or any attribute into our relational design? Multi-valued attribute can be represented by double dotted ovals in an ER Diagram. Following are the rules to follow for transformation of multi-valued attribute into relational model: An Entity type with a multivalued attribute is transformed into two relations One relation contains the entity type and other simple attributes whereas the second relation has the multivalued attribute. In this way only single atomic value is stored against every attribute. The primary key of the second relation is also the primary key of the second relation. So, in the second relation the primary key is the combination of two attributes. All values are accessed through reference of the primary key that also serves as foreign key.

  What is Software Testing? Software testing is a phase of software development life cycle. Basically Software testing process starts when other phases completed in software development. Software testing aims to check certain aspects of a software system (or a part of it). On the other hand, it is to test the working of software product matches the expected output in different environment or in different configurations. Software testing is to ensure the features of the software is gathered and completed. Importance of Software Testing? A developer task is to convert the requirement into code, before handing over it to the client, make sure its bug free. Importance of Software can be define as the client or QA person making sure that the delivered software is the right software. Significance of Software Testing: Software in different industries e.g. medicals, air planes, banking are very crucial if a bug appears you are risking the lives. Consider the followin

  or more in formal way degrees of relationship. zero one many