I have two tables. A table called users (content speaks by it self) and a table called groups. Since i want every user to be able to be a member of several groups and, of course, a group to have several users i have made a junction table called jt. The junction table contains userId's and groupId's according to the user-group bindings. The primary key(identity) in the junction table is a int named jtId. Now i want to take out all posts from the junctiontable and the corrresponding userName (s) from the users-table and the corresponding groupName from the groups-table. Can somebody please help me to make a SQL command that will di that for me. I have tried with INNER JOIN and several SELECTS in the same command. Thanks in advance, Greetings from Esben
Looking for some help here, so thanks for any input. I'm a painfully new newbie to SQL scripting.Situation: I have a simple database to handle an organization's events. Those events are categorized and may have more than one category assigned to each event. I need a maintenance Web Form to update their events.Set Up (so far): I have a CATEGORIES table. It has an auto incrementing UID and a Category name field. This table will be updated so infrequently, I plan to update it manually (no need for a maintenance Web Form). Next is the EVENTS table. It also has an auto incrementing UID along with several fields (Title, Location, DateTime, etc.). The junction table is named jEVENTSCATEGORIES. It has its own auto incrementing UID along with 2 fields named for the primary keys (UIDs) in the other 2 tables (EventsID and CategoryID).Goal: On the Web Form, I have a CheckBoxList control that's populated by the CATEGORIES table. One or more categories can be checked for each event. I have a FormView control that allows Edits and Inserts.Need: I need to know the INSERT statement(s) required to insert a new record in the EVENTS table and then to update one or more rows in the junction table (jEVENTSCATEGORIES).My Assumptions: I know how to create SELECTs and INSERTs and whatnot, but I'm not certain how to create a second INSERT statement that is based on a variable (or output) from a previous action. So any help would be MUCH appreciated. Thanks for your time!
Hi i have a junction table(UserGroups) which is linking my users table with my groups table, however when the information is coming back in the format below, instead i want the group names to appear in only one field, instead of repeating the same data, could someone please tell me what i need to change
UserName: Edwin CarolsUserAge: 28JobTitle: ManagerGroupName: AFC Below is my SQL statement; SELECT Users.UserName,Users.UserAge, Users.JobTitle, Groups.GroupName FROM Users INNER JOIN UserGroups ON Users.UserID = UserGroups.UserID INNER JOIN Groups ON UserGroups.GroupID = Groups.GroupID WHERE (Users.UserID = '5')
As an example, I am building an authentication mechanisim that will usedata in the 3 left tables to determine rights to objects in adestination table, diagrammed below. In this structure, multiplerecords in the left tables will point to multiple records in the righttable. Normally, I would approach this problem using junction tables(LeftID, RightID) to create many-to-many joins.However, given the structure of each table is nearly identical (as faras the linking IDs are concerned), I could also use a single junctiontable with columns for each available table ID (LeftID1, LeftID2,LeftID3, RightID). In this table, only two IDs would be utilized perrow (LeftIDx -> RightID).In both designs, the needed rights information is returned from fairlysimple views, thus the end result is equivalent. The advantage to thesecond, multi-ID junction table design, is a simpler databasestructure. However, never using this approach before, I am unsure ofthe potential future performance impacts.Any significant downsides to this second design? Examples of anabbreviated structure follow:Data Tables-----------LeftTable1LeftID1 (int)Data1LeftTable2LeftID2 (int)Data2LeftTable3LeftID3 (int)Data3DestinationTableRightID (int)DataLinking tables option 1-----------------------JunctionTable1LeftID1RightIDJunctionTable2LeftID3RightIDJunctionTable3LeftID3RightIDLinking table option 2----------------------JunctionID1 (int)ID2 (int)ID3 (int)DestinationID (int)
Hi i have a junction table(UserGroups) which is linking my "users" table with my "groups" table, however when the information is coming back in the format below, instead i want the group names to appear in only one field, instead of repeating the same data, could someone please tell me what i need to change.
UserName: Edwin CarolsUserAge: 28JobTitle: ManagerGroupName: AFC Below is my SQL statement; SELECT Users.UserName,Users.UserAge, Users.JobTitle, Groups.GroupName FROM Users INNER JOIN UserGroups ON Users.UserID = UserGroups.UserID INNER JOIN Groups ON UserGroups.GroupID = Groups.GroupID WHERE (Users.UserID = '5')
Hi i have a junction table(UserGroups) which is linking my "users" table with my "groups" table, however when the information is coming back in the format below, instead i want the group names to appear in only one field, instead of repeating the same data, could someone please tell me what i need to change.
UserName: Edwin Carols UserAge: 28 JobTitle: Manager GroupName: AFC
Below is my SQL statement;
Code:
SELECT Users.UserName,Users.UserAge, Users.JobTitle, Groups.GroupName FROM Users INNER JOIN UserGroups ON Users.UserID = UserGroups.UserID INNER JOIN Groups ON UserGroups.GroupID = Groups.GroupID WHERE (Users.UserID = '5')
Hi all, This is a bit of a general question regarding SQL Server link tables that i hope someone can find the time to answer.
I am looking for the best practice. If I have 3 tables
1) tblCompetition 2) tblTeams 3) tblTeamsInCompetition (this is the link table)
I know the link table should have a related CompetitionID and TeamID, but should the link table also have a primary key that is an identity autoincrement by 1 just as you would with the other two tables. In Access I have never done this, however in SQL Server I have read that you should do this (but now I can't find the documentation again which prompts me to ask the question here).
Thanks for taking the time to answer this question.
This seems like such a simple problem but I am new developer even through I have been on the administration end of things for some time. I will go into more detail about my tables and there relationships below. Anyway, I am trying to create a many-to-many relationship within ms sql server 2005. I have created both of my primary tables and also a junction table per the directions on microsoft's website all per ms's instructions as stated here...
At then end of these instruction it states as a NOTE: The creation of a junction table in a database diagram does not insert data from the related tables into the junction table. For information about inserting data into a table, see How to: Create Insert Results Queries (Visual Database Tools).
and these directions do not go into detail on how to do an insert on a junction table. And I cant find out how to do this anywhere on the internet... I did create a T-SQL INSERT statement in a trigger as listed below but I end up getting an error AS LISTED BELOW....
Here is how I set everything up...
PetitionSet table consists of:
PetitionSetID int auto-increment primary key PetitionSetName varchar(50) no nulls PetitionSetScope varchar(50) no nulls
the Petition table consists of:
PetitionID int auto-increment primary key PetitionSetID int no nulls PetitionName varchar(50) no nulls
the SetToPetitionJunction table consists of: PetitionSetID int PetitionID int
And, there is a composite key made up of both the PetitionSetID and PetitionID fields.
I have created the foreign key relationships with DEFAULT VALUES from the SetToPetitionJunction table to each column's respective corresponding column in each of the tables: PetitionSet and Petition.
The trigger is on the Petition table and it has the following code:
set ANSI_NULLS ON set QUOTED_IDENTIFIER ON go -- ============================================= -- Author: Name -- Create date: -- Description: -- ============================================= ALTER TRIGGER .[SetToPetitionJunctionTrigger] ON .[dbo].[Petition] AFTER INSERT AS BEGIN -- SET NOCOUNT ON added to prevent extra result sets from -- interfering with SELECT statements. SET NOCOUNT ON;
INSERT INTO SetToPetitionJunction (PetitionID, PetitionSetID) SELECT Petition.PetitionID, PetitionSet.PetitionSetID FROM Petition INNER JOIN PetitionSet ON Petition.PetitionSetID = PetitionSet.PetitionSetID
END
I have created an asp.net 2.0 front end to insert values into the PetitionSet table and the Petition Table. And in the detailsview for the Petition table I manually insert the PetitionSetID field to the number that corresponds to an auto-generated number on the primary key of the PetitionSet table. So I am maintaining referential integrity...
The first time it works and inserts one record in the Junction table containing the PetitionSetID from the PetitionSet table and the PetitionID from the petition table.
Then when I try to add in another petition for the same petition set number just like I did the first time and then I get this error...
Violation of PRIMARY KEY constraint 'PK_SetToPetitionJunction'. Cannot insert duplicate key in object 'dbo.SetToPetitionJunction'. The statement has been terminated.
Maybe this is the wrong formum but I've got a question for which you probably have the answer, i hope.
Situation ------------ John is member of Group_A and Group_B Bill is member of Group_B and Group_C Allison is member of Group_A and Group_E
How can I create a query to input Allisons username into table 1 and groupmembership into table 2. Also updating the relationship within junction-table3 must be done automaticaly. I want to avoid duplicate records. The final situation I want is given in red text.
The relationships between the tables are as follows ------------------------------------------------------------- Table1 (PK)ID-Userinfo [ONE] <------------> [MANY] Table3 ID-Userinfo Table3 (PK)ID-GroupInfo [MANY] <------------> [ONE] Table2 (PK)ID-GroupInfo
Table1: UserInfo ------------------------------ (PK)ID-Userinfo UserName 1 John 2 Bill 3 Allison
Can Somebody please show me how to acheive this, using the order details in Northwinddatabase or any other good example. as much details as possible. Many Thanks!
Hi,Does anyone have any suggestions on the best to go about enforcing arelationship between two tables that exist within separate databaseson the same SQL Server instance.
I have the tables tblEmployees and tblProjects.tblProjects has one column called Percentagetime, to hold the percentage oftime by an employee for a project.My Question : Why should we introduce a 3rd table calledtblProjectsAndEmployees?tblProjectsAndEmployees will have1)EmployeeNumber(PrimaryKey in tblEmployees)2)ProjectNumber(Primary key in tblProjects)3)PercentageTimeHaving only the tblEmployees and tblProjects is not sufficient?Kind Regards,Vinodh Kumar P
Hi, I'm working on a database for which I require to have a lot of relations from my Persons table to other tables. I will need my primary key in those other tables: about 10 to 15 tables, to be able to relate to my persons data.
I believe this means I have 10 to 15 clustered indexes on this table. Is this the right way of working? I know too many of this relations to other tables will have impact on performance concerning insert and updates. But I noticed in the adventureworks example it works just this way for the products table.
What is the max limit of this kind of relations? (for reasonably good performance) Should I use triggers instead? - for those with the least user interaction?
I am looking to print the table structure of a Microsoft SQL Server 7 database through the Enterprise Manager Utility. I would like to print it to a plotter but the print options in the Enterprise Manager are inadequate. I believe I will need to use another program to manipulate the object prior to plot due to its size. I have the following tools available:
VB6 Autocad (Do not have Adobe Writer)
Is there a way to get this print object to Autocad or even as a bitmap?
I have spend days researching this and found others with the exact same problem but there are no useful replies as people don't seem to understand our problem. Please read this carefully...
What is the best way to create relationships between new SQL tables? For example, say I want to create a new database with tables for Customer, Orders and Details, how to I relate these tables?
- Edit via the Dataset designer in Visual Studio 2005? - Use the Server Explorer's Table designer in Visual Studio? (not sure how to use the 'relationship' icon) - Use SQL Server Managment Studio Express (SSMSE) Database Diagram - Something else?
I am using Visual Studio 2005 Standard and SQL Server 2005 Express (SP1).
I created a new database in Visual Studio's Server Explorer and then used the Table Designer to create two new Tables (Customers and Orders). I then assigned primary keys but I don't know the best way to relate the tables.
If I create and edit a new dataset, I can graphically drag a relationship between the tables. HOWEVER, this relationship isn't recognized by SQL Server Management Studio Express (SSMSE). I found this out when I tried to create a database diagram, none of the relationships appear in SQL?! This would cause problems when I want to deploy the database to my client.
If however, I START in SSMSE and create the tables there, then open a Database Diagram in SSMSE and graphically link the tables, then Visual Studio will see all the relationships.
I thought it was supposed to be a seamless integration between Visual Studio 2005 and SQL Server 2005. Am I missing something?
What is the best way to setup relationships between one lookup tableand many other tables. The tables did not have any lookup tablerelationships which I am adding. One lookup table is used for same datain several different places.To use one lookup tables with several tables, I had to disable "CascadeUpdate" and only have "enforce relationships for updates and inserts"checked.Any pros/cons?Thanks in advance.P
Hello,I want to be able to view data from 3 tables using the JOIN statement, butI'm not sure of how to do it. I think i don't know the syntax of the joins.Iimagine this is easy for the experienced - but Im not.Allow me to explain:I have 2 Tables: PERSON and SIGNPERSON------PersonNo int (Primary Key)Name varchar(50)StarSign intFavFood intSIGN----StarSign int (Primary Key)StarSignName varchar(50)Relationship: SIGN has a one-to-many relationship with PERSON. The linkingfield is called 'StarSign'.Question 1:I want to display all the peoples names, and their star sign (whether theyhave one or not).Answer 1:SELECT PERSON.Name, SIGN.StarSignNameFROM PERSON LEFT OUTER JOIN SIGN ON PERSON.StarSign = SIGN.StarSign;No problems there. But now I want to do the same thing, but have theirfavourite food displayed as well. So an additional table is needed:FOOD----FavFood int (Primary Key)FavFoodName varchar(50)Relationship: FOOD has a one-to-many relationship with PERSON. The linkingfield is called 'FavFood'.Question 2:I want to display all the peoples names, their star signs (whether theyhave one or not), and their favourite food (whether they have one or not).Answer 1:???I'm not sure what to do. Notice that I want to use an LEFT OUTER JOIN so ALLthe rows from table PERSON will appear 'irrespective' of whether they haverelated records in the other tables.Jack.
I'm building an application that tracks courses and equivalent courses. For example, say I have course A which a user should get credit for if they have taken equivalent courses. So if a user has taken (course B or course C) AND (course D or course E) he should get credit for Course A. What's the best way to setup a SQL table to create these type of equivalent relationships?
I'm looking for a query I can use to alter table relationships. What I want to do in particular, is to set every relationship to cascade on update. Can anyone point me out to a solution? MSDN seems very vague in this subject.
I'm using Sql Server 2012 Enterprise and have a database with over 400 tables. I am looking at one diagram which contains about 20 (or so) tables and their relationships. When I right-click on a relationship line I only see information about which tables are connected on that line but not on which fields. Can I get that information from the Diagram or can I only get that from the sys tables?
I'm designing a database with 3 tables called Function, Test andScene.A Function has multiple Tests, but a Test has only one Function. Amany to many relationship exists between Test and Scene therefore Ineed a junction table between these two tables - giving 4 tables intotal. The Test table would store a foreign key, the primary key ofthe Function table.There is a problem with design though and that is that Functions andScenes are actually defined before the Test is defined. Therefore itshould be possible to create a Function and add to id its Scenes,before Tests have been defined. In other words, Scenes are as much apart of a Function as they are of Tests. Tests are in fact only ofrelavence to testers. Anyway, to satisfy this scenario, a Junction boxis also needed beween Function and Scene. This creates a loop betweenall tables.Is this a good approach? Any other suggestions or advice on thematter? Any advice regarding data integrity?Thanks,Barry
I'm going through my tables and rewriting them so that I can create relationship-based constraints and create foreign keys among my tables. I didn't have a problem with a few of the tables but I seem to have come across a slightly confusing hiccup.
Here's the query for my Classes table:
Code:
CREATE TABLE Classes ( class_id INT IDENTITY PRIMARY KEY NOT NULL,
This statement runs without problems and I Create the relationship with my Users table just fine, having renamed it to teacher_id. I have a 1:n relationship between users and tables AND an n:m relationship because a user can be a student or a teacher, the difference is one field, user_type, which denotes what type of user a person is. In any case, the relationship that's 1:n from users to classes is that of the teacher instructing the class. The problem exists when I run my query for the intermediary table between the class and the gradebook:
Code:
CREATE TABLE Classes_have_Grades ( class_id INT PRIMARY KEY NOT NULL,
Query Analyzer spits out: Quote: Originally Posted by Query Analyzer There are no primary or candidate keys in the referenced table 'Classes' that match the referencing column list in the foreign key 'Classes_have_gradesFKIndex2'. Now, I know in SQL Server 2000 you can only have one primary key. Does that mean I can have a multi-columned Primary key (which is in fact what I would like) or does that mean that just one field can be a primary key and that a table can have only the one primary key?
In addition, what is a "candidate" key? Will making the other fields "Candidate" keys solve my problem?
Ok, so I open up a book on beginning sql and it discusses relationships.There is something that appears wrong. I am not understanding how the book is describing the one to one relationship. In it's figure, it shows that the same agency can have two different artist id's. But according to it's definition of one to one list can be related from both tables.Can someone explain this further please?Thanks in advance.
How do you show many to many relationships in ASP.NET with datasources? I can retrieve the information from the database easily but I can't manage to save that information into a variable so that i can then call for only information in the M2M table related to the ID Key I want. For example..1 <asp:Label ID="lblTestLabel" Text='<%# DataBinder.Eval(Container.DataItem, "title_id") %>' Runat="server" /> 2 3 <script language="VB" runat="server"> 4 sub Page_Load(sender as Object, e as EventArgs) 5 Dim lblTitleID As Label = Repeater1.FindControl("lblTestLabel") 6 Response.Write(lblTitleID.text) 7 End Sub 8 </script>
When I try to run this script it dosn't work and I get the error: System.NullReferenceException: Object reference not set to an instance of an object. For line 6 of the code above. Is there a way to just retrieve information from a datasource without storing information into a label first? PS: I use sqldatasource tags to retrieve information like:1 <asp:SqlDataSource ID="DataSet1" runat="server" 2 ConnectionString="Driver={MySQL ODBC 3.51 Driver};server=localhost;database=;user=;pwd=;option=3;" 3 ProviderName="System.Data.Odbc" 4 SelectCommand="Select * from titles order by title_id"> 5 </asp:SqlDataSource>
Can someone help me sort something out. Suppose we have two tables in a database.One is named Person, and one is named Birthday. Is this a many to many relationshipor a 1 to many relationship? Person has many birthdays. Example. Joe Schmoe has a birthday for every year of his life. birthday(7/11/1976) has many People (Many people have a birthday on 7/11/1976.
Is there any easy way of getting all the relationships for the tables in aSQL server db? I've looked through Google and the Books online but I'm barely scratching the surface on the systables. I know I can go to each individual table and get the dependencies or even print out the diagram through Enterprise Manager but I really don't want to have to type out all the primary/foreign keys for 100+ tables. Any help on getting this data either through a 3rd party software or querying the systables would be great.
We have a table with approximately 150 colums and 2/3 of them are bit datatypes. We do not expect much activity on this table. Does it make sense to separate it into a few tables instead of 1 with one-to-one relationships? Will the join(s) significantly slow down our web application? Thank you
My hosting servers have "myLittleAdmin" installed. I am new to ms sql I have some experience with Access but I have never set up Relationships inside the database server. I have always just relied on my application logic to call the relations. What is the benefit to setting up relationships in sql, if any?
