I have a few questions here about designing a database:
1. What is normalisation and de-norminalisation?
2. A quote:
normalisation has a series of steps (or rules) called forms the more steps you take, the more normalised your tables are......If you use the first 3 steps you would say that the tables are in their Third normal form
What is all that about - whats forms got to do with tables or what is he trying to say in the above quote?
3. When would you decide to create a new table in a database - i.e. what rules does everyone follow to say "ok i better capture this data in a new table and create a relationship to another table"
Hey guys, this is my first post here. I just joined recently and I am loving the videos as they've really helped me step into ASP.NET and VB. Just some background, I used to be a CS major several years ago and programmed in Java and C, though I only went through 2 years before I moved majors. I didn't like the focus of my universities program, and decided to pursue other options. Ironically, I am now delving back into programming, but with a focus on web development, hence learning VB and ASP.NET. Anyways I am developing my first web application and I needed some help.Basically, what the program does is allow users to login to this web site and then store private information, which they can then access at a later time from any computer that is connected to the web. I have already setup user membership by following the video (lesson 8 of the ASP.NET series - Securing your Web site with Membership and Login Controls) from the Learnvisualstudio.net series. I can login to my site just fine, as well as creating a new user etc. The next step is designing the SQL database, and setting up the page that retrieves a users data, allowing them to view the private information they've stored, as well as to edit, create, and delete information.Unfortunately, while I can see the broad method of doing this, I am a bit lost in actually implementing it. The first stumbling block I am coming across is the SQL database itself. I have attached an image of how I have the database designed so far. Note that the aspnet_user table is the one that ASP.NET creates automatically when you enable membership controls and such.So basically, a user logs in, and they are greeted with a list of all of the "stickies" they have created. Each sticky has a title, as well as up to 4 fields, and you can enter the name of the field, as well as enter the actual data. It's foreign key ties back to the UserId that ASP.NET already created. The user can also organize their stickies into categories, hence that table. The Settings table will be where a users settings will be saved, such as which view mode they prefer etc. At this stage of development, that table is un-important and un-developed.So on to some of my questions. As it is designed now, there will be one table with every users stickies, as well as categories, and when a user logs in, the program will look at the category and stickies tables, and grab the ones that are associated to the users UserId. So one of my first questions is; is this a good design? I ask this from a security standpoint as well as a speed and efficiency standpoint. I want this site to be able to support at least 50,000 to 100,000 users, each with any number of "stickies" and "categories" With that size of a user base, would each user be looking at massive load times because the program would have to go through a very large table to grab only the ones that are linked with the users UserId? Say I have 50,000 users, and each user has 5 "stickies", that means that my user_stickies table would have 250,000 rows of data, and the program would be trying to find only 5 of those. Is this a really inefficient way of doing this? Should each user have their own category and stickies table? If so, how would I go about doing this? And in that case, instead of having a couple giant tables, my SQL DB would instead have a ton of tables, is this even any better?I have other questions, but I guess I'll start with this. What are your guys' thoughts? I am a newbie, so this may be a silly set of questions. I try to read up and research as much myself as I can, but sometimes you have so much information thrown at you at once its hard to grab out the specific answers you need.
I’m trying to design a database that allows the users to give each individual client/company unlimited addresses and salutations. I can build the design that accommodates this, but I cannot figure out how to handle them knowing which salutation to use with a mailing they might do to the clients.
I have put the Company Name and Position (title) in the address table so that when doing a mailing the company name and title are associated with the company address being mailed too. But again, I’m not sure how they would choose a salutation if they have many choices.
Hi, I designed the database and there are two points I'm not sure that my design was correct: 1) In my search engine (in interface) i have an expression builder and user can save the expression he created. In this case don't chreate view in database, but I have a table named "Expressions" which saves expression name and expression. The reason I made it was: If I create view it doesn't make db to work faster because the select query in view runs every time when view was opened, but it makes my code more generic . But isn't it a design error?
2) I save 3 reserved fields in each table, and I don't know if I'll use them some day. The reason: adding a column to database is heavy operation. But isn't it a design error?
Hello gurus:Hopefully someone can shed some light on some questions I have. I amtasked to build an application that will schedule and track tasks. Ifirmly believe in not reinventing the wheel however also feel thatcustomizing is certainly not out of the question.I am looking to build something in ASP (or .NET) that can allow anindividual to work "disconnected" from the network while stillaccessing a database (MSDE?) that will sync with SQL 2000 oncere-connected. I have built multiple db apps that are strictly webbased and consider myself somewhat knowledgeable (read.. dangereous)SQL/ASP dude. I understand that for a stand-alone client app I mayhave to use .NET and load the framewsork on the client in order to runthe dynamic pages for database updates. Here are my questions:1) Is there a way for SQL server to "replicate" its tables into aschema/data recognized by MSDE (i.e. generate the "mother ship" tablesand schema first, then use SQL Server to automatically create (export)the client MSDE tables)2) are there tools to manage MSDE so one can see what the heck is inthere? I understand Enterprise manager will not work in this regard.3) Are there any resources (documents, tutorials etc..) for datareplication (i.e. dbsync from MSDE up to MSSQL and vice-versa)4) Am I wasting my time doing this from scratch because there isalready something out there that does all this that is moderatelypriced and customizable?Thanks for your attention and consideration.Eric B
I am trying to design a database for storing trule/false questions. I have no need to store any thing like chapters are topic. I want to just design a bare minimum tables for just storing questions and its responses. So does the following tables and fields suffice to achieve that?.
Questions_table(id(autogenerated),course_id,Questi on(text type)) id field uniquely identify each question, course_id(ex:CRS235) is used to identify which course a particular question belongs to, and Question filed store actual question.
Response_table(id,response) Response field is of int type, 1 for correct answer, 0 for wrong answer. I am not storing options for each question because every question has same options that is True/False.
So, will this work. Please advice and I would appreciate if any one can point me to a good resource on the web.
Ok, I'm doing a football database for fixtures and stuff. The problem I am having is that in a fixture, there is both a home, and an away team. The tables as a result are something like this:
It's not exactly like that, but you get the point. The question is, can I do a fixture query which results in one record per fixture, showing both teams details. The first in a hometeam field and the second in an away team field.
Fixture contains the details about the fixture like date and fixture id and has it been played
Team contains team info like team id, name, associated graphic
TeamFixture is the table which links the fixture to it's home and away team.
TeamFixture exists to prevent a many to many type relationship.
Make sense? Sorry if this turns out to be really easy, just can't get my head around it at the mo!
We are negotiating with a vendor and we have a few questions:1) From a licensing point of view, what is a database? Can we installmultiple copies of SQLServer on one box? In that case, would eachcopy be a different database?2) Within a single SQL Server installation, I can create multipledatabases, as listed in the Enterprise Manager. I can switch amongthem using "use ..." commands. Would these be treated as differentdatabases?3) We have copies of our transactional database in identicaldevelopment, QC, and production environments. Is this a singledatabase, or 3 databases?
I'm new to databases but not to programming in general. I've got a few applications which currently sit on a single PC and read/update a particular XML file on the box. The applications are C# apps and use FileSystemWatchers and a mutex to keep watch for changes and update the XML file as needed. It has worked reasonable well for me.
Now, I need to run these applications on separate machines, so it seemed a good point to consider moving toward a database solution.
I'm hoping that there is a straightforward solution using SQL Server that will ensure that my applications alway have the current view of the world. I had run into instances with my existing setup where once in a while an application thought its DataSet was up to date, but wasn't.
Can someone point me in the right direction to implement the solution? I suspect that this is a really common need for lots of programs that are distributed. I'm still quite a newbie with databases and SQL Server, so I'm not even sure I'm using the right terms to describe things.
Our company is looking to move to a more robust database platform/setup, and it looks like sql 2005 + database mirroring is what we are looking for. First I have some questions about it.
Can a server that is functioning as a mirror for one database be the primary server for a seperate database? Basically think of a triangle of three sql servers, each serving as a primary server for a specific database, and using the next server in the triangle as a mirror for that specific database. To be more specific:
Server 1, Primary Database A, Mirroring Database C Server 2, Primary Database B, Mirroring Database A Server 3, Primary Database C, Mirroring Database B
If that is possible, how many witness servers would be needed to accomplish the above topology? On that note, how robust hardware wise should the witness server be?
On a completely seperate note, what method is recommended for interconnecting these servers? Is gigabit ethernet fast enough, or does it require something like fibre channel or infiniband?
I actually work in an organisation and we have to find a solution about the data consistancy in the database. our partners use to send details to the organisation and inserted directly in the database, so we want to create a new database as a buffer database to insert informations from the partners then make an update to the main database. is there a better solution instead of that?
Hello everyone,I have a webcontrol that uses database-structures alot, it uses the system tables in SQL to read column information from tables. To ease the load of the SQL server I have a property that stores this information in a cache and everything works fine.I am doing some research to find if there are anyway to get information from the SQL server that the structure from a table has changed.I want to know if a column or table has changed any values, like datatype, name, properties, etc.Any suggestions out there ?!
I have a system that basically stores a database within a database (I'msure lots have you have done this before in some form or another).At the end of the day, I'm storing the actual data generically in acolumn of type nvarchar(4000), but I want to add support for unlimitedtext. I want to do this in a smart fashion. Right now I am leaningtowards putting 2 nullable Value fields:ValueLong ntext nullableValueShort nvarchar(4000) nullableand dynamically storing the info in one or the other depending on thesize. ASP.NET does this exact very thing in it's Session State model;look at the ASPStateTempSessions table. This table has both aSessionItemShort of type varbinary (7000) and a SessionItemLong of typeImage.My question is, is it better to user varbinary (7000) and Image? I'mthinking maybe I should go down this path, simply because ASP.NET does,but I don't really know why. Does anyone know what would be the benifitof using varbinary and Image datatypes? If it's just to allow saving ofbinary data, then I don't really need that right now (and I don't thinkASP.NET does either). Are there any other reasons?thanks,dave
Hi All,Can u please suggest me some books for relational database design ordatabase modelling(Knowledgeable yet simple) i.e. from which we couldlearn database relationships(one to many,many to oneetc.....),building ER diagrams,proper usage of ER diagrams in ourdatabase(Primary key foreign key relations),designing smallmodules,relating tables and everything that relates about databasedesign....Coz I think database design is the crucial part of databaseand we must know the design part very first before starting up withdatabases.....Thanks and very grateful to all of you....Vikas
The ReorderList control has driven me to desperate ends tonight. I found that it will only work if my database has a field (OrderID in this case) of type int that it can use to keep track of the order. The problem is that I'm not using the ReorderList control for inserting into the database. This requires me to keep track of the OrderID myself and I have found that simply setting the OrderID field as the "Identity" will cause it not to work.
Common sense tells me that using the Identity is the best way to keep track of a ReorderList because it automatically numbers things as ther're inserted. If something is deleted, it shouldn't matter because it will still be in order even to there's a gap in the numbering.
The only solution I can think of is trying having TWO identity fields in the database, but since that's not possible, a field that mirrors the Identity. Can anyone advise me on how to do that? The below datasource does not insert anything into the OrderID field:
I have a db in SQL server 2000 developer edition. I am using Visual Studio 2005 standard, and also VWD Express. I would like to just access the database that is in SQL server 2000 so I can get on with developing the site, but VS2005 refuses to recognize the instance. It recognizes 2005 instances right away.The services are all running, the network protocols are enabled, uid's/pw all of that is correct. I am getting the "named pipes" error (the named pipes protocol is enabled).Any suggestions? I'd really rather just work with the db as-is in SQL 2000. But I can't get it to connect. I can connect to it if I export it to SQL 2005, (on the same development machine) but can't get the stored procs over to the 2005 db. So my web app is not finding the stored procs and won't run.Do I need to uninstall SQL 2005 from this box if I want to use SQL 2000?Thanks,--Donnie
I have an ODBC 3.0 Application on Windows NT Server maintaining aconnection to a SQL Server 2000 database on the same machine. When anerror occurs, I'd like to be able to determine whether the error isserious enough that the database connection has been lost, so I canhave the application try to reconnect automatically. My understandingis that any error of severity 20 or above includes a broken connection,but I'm having difficulty retrieving the error severity through ODBC.So my first question is, how do I retrieve the error severity throughODBC?Also, as a test, I stopped the database while my application is stillrunning, and the first error I received had a native error code of 55.There is no 55 error in the sysmessages table, so I'm confused as towhat the severity of the error is. Can anyone shed some light on why Iwould be receiving an error code that is not in the sysmessages table,and where I might be able to find more information about the error?Thanks in advance,Abram
We have SQL 2005 db mirror configured with a witness server for high availability. Node 1 is the principal and Node 2 is the mirror. A nightly job creates a snapshot on Node 2. The snapshot is used for previous day reporting queries. We have now been asked to present another copy of the database for near-time reporting. I thought about possibly adding a peer-to-peer replication as part of my environment but was hoping to see what everyone else out there is doing.
Hi All, I am designing database where few of the master tables will reside in different database or in case different server. Scenario is Server "A" with Database "A" may host the "Accounts" table. Server "B" with Database "B" may host the "Product" table. I am designing database "Project" which will hosted in Server "A". My application requires this master tables [readonly access] as data inserted in my application refers this tables. Also there are reports to be generated which refer this tables. How do i design my database and sql queries? I am thinking of approach of having equivalent tables created in my database and writing service which keep tables in my database in sync. This will ensure good perfomance during transaction and reports as they will need to refer this table locally as opposed to different database or different server.
Any thoughts on above approach?? or any better/standard way for such scenarios ?
Thanks in Advance. Your inputs will be of great help.
Online US Searchable Map of the 50 US States. Users search criteria is the following: Query records by selecting state, county, then record. Each County table has 10-20 tables. All databases combined = 500MB and TLogs = 100MB.
How would you re-design a relational DB where users could query data by state-county-record. Currenty the DB's are created by the County of each state which creates hundreds of DB's in SQLServer with no realtionship to each US state. What would be the best design to ensure good performance, data integrity and maintenance? Would you create 1 DB with all 50 states, create 4 DB's and divide by region(N,S,E,W), 50 DB's of each state or leave it as is with each county it's on DB? Any suggestions would be appreciated.
I have a SQL Server 2005 database (called BDHSE) in a PC which i call PC1. I have a second PC (PC2) and both are within a network (a WLAN).
What i want is to have access to BDHSE from an application in VB6 (APP1) running in PC2. All the INSERT, DELETE, UPDATE records process is done through APP1.
APP1 ia currently running in PC1 and is to be installed on PC2.
I have these questions:
1. What do i need to install in PC2 since all the INSERT, DELETE, and UPDATE is done using APP1? I guess i only have to install the Microsoft SQL Native Client (with all the prerequisites of course) but i am not sure.
2. In the APP1 made in VB6, do i have to change the connectionstring since i am accesing the database which physically is at PC1 and the APP1 will be used in PC2?
3. Any advice you can give me on doing this will be well received.
Hello, I am designing my first database with 5 tables for a demo project and am not sure if it works. an example below.2 of the many things I want visitors to the site to do is find a company by the industry sector they belong to,..andwhat sort of service or products they can supply. For instance a Employment agency maybe under professional services Table 1 Customer Customer_ID = primary key,,,, Sector_ID = Foreign keyComapany Name, Address, Phone, Postcode etcTabel 2 Industry SectorsSector_ID = primary key,,,,Customer_ID= foreign key banking, Education,Prof Services, etc Table 3 Trading ActivityTrading_ID = primary key,,,,Sector_ID = Foreign key, Products_ID= FkEmployment Agent, School, Lawyer etcTable 4 ProductsProducts_ID = primary key,,,,Trading_ID = foreign keySupply frozen foods, transport services, sports goods, etc Table 5 Account Account_ID = primary key,,,,Customer_ID = foreign keyAccount Name, Credit Limit, Payment Terms, Open date, Account contact etc One big point of confusion is, can I have the Customer_ID from the principal Customers tablein every table as a foreign key or must the tables be chained together one after the other as such. Advice appreciatedThanks
Hi, I need a hand with designing a database. I am collecting results from a survey which has the following questions: Call ref? How did you place your support call? Were you satisfied with the amount of time you had to wait until getting acknowledgement of the support call placed? 1 = very satisfied and 10 = very unsatisfied. How happy were you with the customer service you received upon placing the support call? 1 = very unhappy and 10 = very happy.How satisfied were you with the amount of time you had to wait until you heard from an engineer? 1 = very satisfied and 10 = very unsatisfied. How satisfied were you with the time taken to get your problem/query resolved? 1 = very satisfied and 10 = very unsatisfied Did you feel the engineer had enough knowledge to deal with your call? 1 = very good and 10 = not very good Overall how satisfied were you with the support call placed? 1 = very satisfied and 10 = very unsatisfiedIs there anything we can do to improve the quality of the support and service you received? I want to store this in a database. Obviously I want to use best practice for design, normalisation etc. The stumbling block I am coming accross is the fact that each question has a number and each question has a score from 1 to 10 and storing this in the database. Any help appreciated! Thanks Andrew
I am creating database tables for company testimonials. Database columns: name, position, companyname, comment, service we provided. My question is that for each company - may have a multitude of different services from us, and different people with different positions in the same company may make comments. What is best practice for putting this db structure together? Thanks Andrew
Can anyone tell me how can i design database architecture for the Table Category & Product...so that i can make N-level entity relation....I have database in SQL SERVER 2000.
I guess I am confused about something and need some help. I am looking at a database schema for about 20 tables in a database. I noticed that the firstcolumn in each table Is some type of Id. For example StudentId,TestId etc.Where the Id is a unique numeric sequential value. So I have some questions?1- Do these Id's act as what are called indexes for the table?(Unique indexes)2- If the answer to 1 is correct, then how do I create these unique indexes? Is it as simple as declaring the Id column as the primary key and that this value will be generated automatically upon insert? 3- Is it necessary to have an Id column for every table, or may I only do it for a few of them?4. In relation to Question2, what do I need to do, so that the Id column will automatically be created when someone inserts a value into the database table with an ID column. For example here are two sample tables StudentsInfo StudentId<PK> Name Age 1 Mark 33 2 Jill 23 3 Mary 25 PersonalInfo Name<FK> SocialSecurity Address MajorMark 324-444-3342 15 Elm ArtJill 888-888-8998 21 North ScienceMary 876-777-2344 18 Byle Music
Hi,I am planning to create a technical forum for our college. could any one give me an idea of how to design the database for the forum. what table and columns i should have?
I have got a design issue.I have got 4 tables,having relationships.Now,user will edit records and save them,but I want to save the values which were exixsting before they were edited and saved.Implying,if a record is edited 50 times,then the values of each edit needs to be saved.How best ,can I achieve this.
Hi !!We are designing a system where we ask people for their interests and store in into the database and send customize email. Following are the questions:1) Should we use Identity column as Primary Key and CustomerID column? OR we should create Custom CustomerID and use it as Primary Key? (I have read few articles about Identity column as Primary or not Primary, but need little advice what to accept)2) We have a Tables called : Interest & Customer_InterestCustomer Table:CustomerID, Customer Name, Address, Email, Signup DateInterest Table:InterestID, InterestNameCustomer_Interest: (Need suggestion for How to design this)Should Table be design like:Option1: CustomerID, InterestIDOption2: CustomerID, Interest1, Interest2, Interest3, Interest4i.e.Lets Say: Customer table has CustomerA, CustomerB, CustomerCInterest table has Interest I1, I2, I3, I4Lets Say CustomerA Signedup for Interest I1, I2, I3 and CustomerB signed up I1, I4As per Option1:Customer_Interest Table witll haveCustomerA, I1CustomerA, I2CustomerA, I3CustomerB, I1CustomerB, I4ORAs per Option2Customer_Interest (Where Interest Column is bit column..... 1 = Signed up, 0 = Not Signed upCustomerA, 1, 1, 1, 0CustomerB, 1, 0, 0, 1Which way we should design? 3) If we select Option2, and if we are displaying data in ASP.NET Page, will there be any issue if we use 3 tier architecture?Thanks !!!
I am designing an inventory database in which I need some help, I have the following entities:ItemsNotebookWireless CardADSL Modemetc...ModelsAcer centrino 1.6Acer centrino 1.733COM 4x125 hours Wi-fi access50 hours Wi-fi accessetc... PackagesPackage A:Acer centrino 1.63COM 4x125 hours Wi-fi accessPackage B:Acer centrino 1.733COM 4x150 hours Wi-fi accessI made a table for the items having the following fields: Item_ID, Item_Nameand another for the Models having: Model_ID, Model_Name, Item_Type(Foreign Key to Items table)up to this point is this correct?About the packages table, I don't know if it is correct to have a field for each model (one for notebook, other for modem, and other for wireless card) like this it would be like having 3 foreign keys to the same table but nothing distinguishes themI don't know how to relate the packages and the models table.Any recommendations for a proper design for those entities?
