Primary Key And Foriegn Key?
Dec 25, 2006What is a Primary Key and Foriegn Key and how do they relate? Also, if I have 18 tables...how do I know the tables relate to another. Thanks.
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Primary Key + Foriegn Key
Nov 12, 2007help needed,
sorry for such a basic querry please help me.
i have created 2 tables
both of them has different primary keys
now in first table there is also a refernece for primary key of second table
1) how do i make these both primary keys autoincrement
2) how do i make refernce to primary key of second table
like
table1
itemid itemrate itemcode itemdesscriotion
table2
productid itemid purchaseinvoice invoice amount
also kindly direct me to some quick and easy tutorials on SQL
thanks all for your help.
Foriegn Key
Jan 17, 2006please tell me how to make a foreign key in Ms SQL7
View 3 Replies View RelatedForiegn Key Restraint
Jan 25, 2000Here is a table structure, with 2 contrainst applied to the same columns. Can this possible cause a problem.
CREATE TABLE dbo.app_person
(
appid int NOT NULL,
source char(1) NOT NULL,
first char(16) NULL,
mi char(1) NULL,
last char(24) NULL,
suffix char(4) NULL,
ssn char(9) NULL,
dob datetime NULL,
marital_status decimal(1,0) NULL,
housing char(1) NULL,
mortgage_holder char(20) NULL,
mortgage_payment decimal(9,2) NULL,
auto_holder char(20) NULL,
auto_account char(16) NULL,
auto_balance decimal(9,2) NULL,
auto_payment decimal(9,2) NULL,
de_datetime datetime NULL,
de_clerk char(10) NULL,
excl_other_income bit DEFAULT 0 NOT NULL,
pre_housing char(1) NULL,
same_area bit DEFAULT 0 NOT NULL,
income_type decimal(2,0) NULL,
other_income_type decimal(2,0) NULL,
relationship decimal(2,0) NULL,
line_of_work bit DEFAULT 0 NOT NULL,
selected_bureau_id decimal(1,0) NULL,
excl_income bit DEFAULT 0 NOT NULL,
CONSTRAINT PK_app_person PRIMARY KEY NONCLUSTERED (appid,source),
CONSTRAINT IX_lnapp100 UNIQUE NONCLUSTERED (appid,source),
CONSTRAINT FK_lnapp100_lnapp000 FOREIGN KEY (appid) REFERENCES dbo.app_main (appid)
)
Error While Trying To Save A Foriegn Key Relationship
Feb 6, 2008Hi
I have a table called ClientPlan and in which PlanId is the Primary key. another table called ClientSources1 and i have a column called planId.. and i am trying to set that as Foriegn key so that if i delete a record in the ClientPlan table i want the record to be deleted in Clientsources too.. i have tried settting the Foreign in the clientsources table for ClientPlan to Cascade update and delete.. but that doesnt work...and i get the error below...
ClientPlan' table saved successfully'ClientSources1' table- Unable to create relationship 'FK_ClientSources1_ClientPlan'. Introducing FOREIGN KEY constraint 'FK_ClientSources1_ClientPlan' on table 'ClientSources1' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints.Could not create constraint. See previous errors.
any help will be appreciated.
Regards
Karen
HELP! Synchronize Db And Maintain Foriegn Key Relations?
Jan 30, 2007I have to synchronize 2 databases hourly but am having difficulty maintaining foreign key relations. These tables use auto-increment columns as primary keys, with child records in other tables related with foreign keys. I can't change the way the local software uses primary or foreign keys as it is hardcoded in the local app. (microsoft retail management system)..(however the web-remote app is easily customized). I am using CDB synchronizer to sync the two databases because the remote one is mysql.
Example tables layout:
Items table has auto-increment primary key 'id'
TransactionEntry table has its own auto-increment primary key 'id' and a foreign key 'item_id'
Example of how remote and local database foreign key relations are incorrect after sync using CDB synchronizer:
8:00am -first installation of database-'item' tables auto-increment 'id' columns match with id last record value of '6'
locally the following products are added:
11001 short sleeve t---gets added with primary key in 'item' table 'id' of '7'
11002 long sleeve t----gets added with primary key in 'item' table 'id' '8'
remotely the following products are added:
21001 hipster jeans- --gets added with primary key in 'item' table 'id' of '7'
31001 overalls---gets added with primary key in 'item' table 'id' '8'
remotely someone orders 21001..so TransactionEntry table records sale of "item_id" of '7', but after synch with our local server,
product with "item_id" of '7' is "short sleeve t".
9:00 -synch takes place...item_id foreign key isn't accurate because of independent auto-increment values..
whenever a product is ordered, the TransactionEntry table will record the product's ID column thats available in it's own local copy... after synch, the 'item_id' field will not match the 'Item' table id field and the data about the transaction's product is lost.
I have read of solutions involving staging/temporary tables to cascade update foreign keys before synching into main database, but hopefully there is a more elegant solution for this. If this is only way, will it be reliable? foreign key mix-match seems like could cause havoc.
Loading Tables With Foriegn Key Contraints
Aug 31, 2006Hi,
I am having trouble loading tables (within the same data flow) that have a foriegn key relationship defined between them. For instance:
Table A is a parent (one side of the relationship) to Table B (many side of the relationship).
I am trying to load Table A first within the data flow and then Table B after, but I get the following error:
[OCMD EntityRole Insert [2666]] Error: An OLE DB error has occurred. Error code: 0x80040E2F. An OLE DB record is available. Source: "Microsoft SQL Native Client" Hresult: 0x80040E2F Description: "The statement has been terminated.". An OLE DB record is available. Source: "Microsoft SQL Native Client" Hresult: 0x80040E2F Description: "The INSERT statement conflicted with the FOREIGN KEY constraint "FK_EntityRole_Entity". The conflict occurred in database "ODS", table "dbo.Entity", column 'EntityGuid'.".
I am currently using OLE DB commands to perform the inserts, I load table A and move on to then load Table B, I can see the records in Table A before trying to load Table B but for some reason Table B load still fails.
I was thinking maybe this has something to do with the transaction setting or Isolation level but have played with this to no avail (currently everything is the default - supported/serializable). Also, I am thinking maybe because the OLE DB commands are creating two seperate connections (they are using the same connection manager) the second one is unable to see the transactions from the other (first) connection (Table A)?
Is there a way around this without dropping (disabling) forigen keys before the load and adding them back in after? Would like to avoid this?
I would also like to avoid reading the data source multiple times. Everything I need is in the one source so I would like to populate multiple tables from the one source data stream instead of reading the same data 2,3 or 4 times etc.
Seems to me there must be a simple explanation/solution for this but I'm stuck at this point?
P.S.
I was intially using OLE DB destinations (because they are much faster) and was having the same issue, which made sense because the OLE DB destinations do not let you pass the data stream on so I had to multi cast to the destinations so they were loading at the same time. I would rather use the OLE DB destinations so if you have any ideas around how I could do this using those components that would be appreciated too!
Thanks!
WHY DO FORIEGN KEYS HAVE TO BE UNIQUE OR HAVE A CONSTRAINT?
Oct 9, 2007How do I go about protecting rows from deletion in this scenerio?
Rule 1 The Administrator Users Account may not be deleted
Rule 2 All Groups have Administrator as a member, and the Administrator cannot be removed.
Rule 3 All Groups have the Administrators Group as a member, and the Administrators Group cannot be removed.
Four tables:
Users Table (
UID bigint Identity seeded with 1234 Primary key
UserID varchar(30) NOT NULL UNIQUE
)
INSERT FIRST RECORD (this record needs to be protected from deletion)
UID = 1234
UserID='Admininstrator'
INSERT FIRST RECORD (this record and others can be deleted)
UID = 1235
UserID='Test User 1'
Groups Table (
GID bigint Identity seeded with 1234 Primary key
GroupName varchar(30) NOT NULL UNIQUE
)
INSERT FIRST RECORD (this record needs to be protected from deletion)
GID = 1234
UserID='Admininstrators'
INSERT SECOND RECORD (this record and others can be deleted)
GID = 1235
UserID='Test Group 1'
Group_Members Table (
GID bigint NOT NULL //points to the group's ID and can't be unique
UID bigint NOT NULL //points to the members UserID and can't be unique
)
INSERT FIRST RECORD (this record needs to be protected from deletion because UID points to the Administrator)
GID = 1234
UID = 1234
INSERT SECOND RECORD (this record and others can be deleted because UID does not point to the Administrator.)
GID = 1234
UID = 1235
Group_Group_Members Table (
GID bigint NOT NULL //points to the group's ID and can't be unique
GGID bigint NOT NULL //points to the group members GID and can't be unique
)
INSERT FIRST RECORD (this record needs to be protected from deletion because GGID points to the Administrators Group.)
GID = 1234
GGID = 1234
INSERT SECOND RECORD (this record and others can be deleted because GGID does not point to the Administrators Group.)
GID = 1234
GGID = 1235
I have tried using foriegn keys, constraints an every thing else, but I hit a brick wall because FK requires the ke to be primary (btw is UNIQUE).
Any help would be appreciated.
Data Table Foriegn Key Problem
Aug 26, 2007I am just learning how to program in SQL, so please be patient with me
ok, here it is, i am getting the following errors with my script when i try to execute, and although i realize that this is not the best style to write my script in, i am trying to learn why this is erroring. the errors are:
Msg 1769, Level 16, State 1, Line 9
Foreign key 'Employee2Job_Title' references invalid column 'Title' in referencing table 'Employee'.
Msg 1750, Level 16, State 0, Line 9
Could not create constraint. See previous errors.
now i realize that the second error is because of the first, and that if i can fix the first, the second will go away. Thanks for the help.
Here is my script
use inventory
go
CREATE TABLE Job_Title
(Job_Title_Title char(25) NOT NULL ,
Job_Title_EEO1_Classification char(25) ,
Job_Title_Job_Description Varchar(45) ,
Job_Title_Exempt_Status Varchar(15)
, PRIMARY KEY (Job_Title_Title)
);
CREATE TABLE Employee
(Employee_Emp_ID integer NOT NULL ,
Employee_last_name varchar(15) ,
Employee_first_name varchar(15) ,
Employee_address varchar(30) ,
Employee_city varchar(15) ,
Employee_state char(2) ,
Employee_Telephone_area_code char(3) ,
Employee_Telephone_number char(8) ,
Employee_EEO1_Classification char(25) ,
Employee_Hire_Date char(8) ,
Employee_Salary char(6) ,
Employee_Gender Varchar(1) ,
Employee_Age char(2) ,
Employee_Title char(25)
, PRIMARY KEY (Employee_Emp_ID)
, constraint Employee2Job_Title FOREIGN KEY (Title
) REFERENCES Job_Title
);
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(1, 'Edelman', 'Glenn', '175 Bishop Lane', 'La Jolla', 'CA', 619, '555-0199', 'Sales Workers', 10/7/2003, 21500.00, 'M', 64, 'Cashier')
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(2, 'McMullen', 'Eric', '762 Church Street', 'Lemon Grove', 'CA', 619, '555-0133', 'Sales Workers', 11/1/2002, 13500.00, 'M', 20, 'Bagger')
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(3, 'Slenj', 'Raj', '123 Torrey Drive', 'North Clairmont', 'CA', 619, '555-0123', 'Officials & Managers', 6/1/2000, 48000.00, 'M', 34, 'Assistant Manager')
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(4, 'Broun', 'Erin', '2045 Parkway Apt 2b', 'Encinitas', 'CA', 760, '555-0100', 'Sales Workers', 3/12/2003, 10530.00, 'F', 24, 'Bagger - 30 hours/wk')
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(5, 'Carpenter', 'Donald', '927 Second Street', 'Encinitas', 'CA', 619, '555-0154', 'Office/Clerical', 11/1/2003, 15000.00, 'M', 18, 'Stocker')
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(6, 'Esquivez', 'David', '10983 North Coast Highway Apt 902', 'Encinitas', 'CA', 760, '555-0108', 'Operatives (Semi skilled)', 7/25/2003, 18500.00, 'M',25, 'Asst. - Butchers & Seafood Specialists')
Insert INTO Employee (Emp_ID, Last_name, First_name, Address, City, State, Telephone_area_code, Telephone_number, EEO1_Classification, Hire_date, Salary, Gender, Age, Title) Values
(7, 'Sharp', 'Nancy', '10793 Montecino Road', 'Ramona', 'CA', 858, '555-0135', 'Sales Workers', 7/12/2003, 21000.00, 'F', 24, 'Cashier')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Accounting Clerk', 'Office/Clerical', 'Computes, Classifies, records, and verifies numerical data for use in maintaining accounting records.', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Assistant store manager', 'Officials & Mangers', 'Supervises and coordintes activities of workers in department of food store. Assist store manager in daily operations of store.', 'Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Bagger', 'Sales Worker', 'Places customer orders in bags. Performs carry out duties for customers.', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Cashier', 'Sales Worker', 'Operates Cash register to itemize and total customers purchases in grocercy store', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Computer Support Specialist', 'Technician', 'Installs, Modifies, and makes minor repairs to personal computer hardware and software systems and provides technical assistance and training to system users.', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Director of Finance & Accounting', 'Officials & Mangers', 'Plans and directs finance and accounting activites for Kudlser Fine Foods.', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Retail Asst. Bakery & Pastry', 'Craft Workers (Skilled)', 'Obtains or prepares Bakery and Pastry items requested by customers in retail food store.', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Retail Asst. Butchers and Seafood Specialists', 'Operatives (Semi skilled)', 'Obtains or prepares Meat and Seafood items requested by customers in retail food store.', 'Non-Exempt')
Insert into Job_Title (Title, EEO1_Classification, Job_Description, Exempt_Status) Values
('Stocker', 'Office/Clerical', 'Stores, prices, and restocks merchandise displays in store.', 'Non-Exempt')
Can I Add A Foriegn Key On A Indexed View To Reference Other Table
Nov 8, 2006Is there anybody familiar with indexed view here?
Can I add a foriegn key on a indexed view to reference other table?
Thanks!
SS 2005 Express- Allowing Null Values And Foriegn Key Constraints
Dec 28, 2006Hello,I have a foreign key constraint between two tables (Appointments andMissedAppointmentReasons) and I'd like to allow null values in Appointmentstable for the field containing the MissedAppointmentReason, but currently, Iget a Foreign Key Constraint Error when I try to add a record to theAppointments table.Any ideas how I can have the null values but still maintain the Foreign KeyConstraint?Thanks!Rick
View 3 Replies View RelatedConvert Composite Primary Key Into Simple Primary Key
Jan 11, 2007Uma writes "Hi Dear,
I have A Table , Which Primary key consists of 6 columns.
total Number of Columns in the table are 16. Now i Want to Convert my Composite Primary key into simple primary key.there are already 2200 records in the table and no referential integrity (foriegn key ) exist.
may i convert Composite Primary key into simple primary key in thr table like this.
Thanks,
Uma"
Adding Primary Key To A Table Which Has Already A Primary Key
Aug 28, 2002Hi all,
Can anyone suggest me on Adding primary key to a table which has already a primary key.
Thanks,
Jeyam
Auto Incremented Integer Primary Keys Vs Varchar Primary Keys
Aug 13, 2007Hi,
I have recently been looking at a database and wondered if anyone can tell me what the advantages are supporting a unique collumn, which can essentially be seen as the primary key, with an identity seed integer primary key.
For example:
id [unique integer auto incremented primary key - not null],
ClientCode [unique index varchar - not null],
name [varchar null],
surname [varchar null]
isn't it just better to use ClientCode as the primary key straight of because when one references the above table, it can be done easier with the ClientCode since you dont have to do a lookup on the ClientCode everytime.
Regards
Mike
SQL Server 2008 :: Change Primary Key Non-clustered To Primary Key Clustered
Feb 4, 2015We have a table, which has one clustered index and one non clustered index(primary key). I want to drop the existing clustered index and make the primary key as clustered. Is there any easy way to do that. Will Drop_Existing support on this matter?
View 2 Replies View Related4 Key Primary Key Vs 1 Key 'artificial' Primary Key
Jan 28, 2004Hi all
I have the following table
CREATE TABLE [dbo].[property_instance] (
[property_instance_id] [int] IDENTITY (1, 1) NOT NULL ,
[application_id] [int] NOT NULL ,
[owner_id] [nvarchar] (100) NOT NULL ,
[property_id] [int] NOT NULL ,
[owner_type_id] [int] NOT NULL ,
[property_value] [ntext] NOT NULL ,
[date_created] [datetime] NOT NULL ,
[date_modified] [datetime] NULL
)
I have created an 'artificial' primary key, property_instance_id. The 'true' primary key is application_id, owner_id, property_id and owner_type_id
In this specific instance
- property_instance_id will never be a foreign key into another table
- queries will generally use application_id, owner_id, property_id and owner_type_id in the WHERE clause when searching for a particular row
- Once inserted, none of the application_id, owner_id, property_id or owner_type_id columns will ever be modified
I generally like to create artificial primary keys whenever the primary key would otherwise consist of more than 2 columns.
What do people think the advantages and disadvantages of each technique are? Do you recommend I go with the existing model, or should I remove the artificial primary key column and just go with a 4 column primary key for this table?
Thanks Matt
Primary Key
Aug 31, 2006Hello all,I'm taking over a project from another developer and i've run into a bit of a problem. This developer had a bad habit of not using primary keys when designing various databases used by his programs. So now i've got approx 1000 tables all of which do not have primary keys assigned. Does anyone know of a tsql script that i can run that will loop through each table and add a primary key field?Thanks in advance?Richard M.
View 2 Replies View RelatedPrimary Key
Aug 16, 2007I have a Department Table.
Can any one tell me its Primary Key.
I have the order
AutoNumber, D + AutoNumber, Code,
Can you help me regarding this.
Because some people never like to use AutoNumber.
That's why I am confused.
Primary Key
Nov 8, 2007Hi..
I'm going to build database of university, but I have problem with primaru key,
This is the situation:
there are many faculities and each one has many departments,
each department has many courses,
each course has many sections..
The problem:
I want to make those fields in the same table and make the primary key generate from other fields,
(i.e)
I want the faculity be integer from 4 digit "Example the first faculity start with 1000 the second 2000 and so on" and the the department of each faculity will generate its value from the faculity number+interger number from 3digit "Example the department of the first faculity start with 1100 and the second on will be 1200 and so on "
the same thing will repeate for courses and sections so the sectionsID will be the primary key.
Do you know hoew this idea can be implement by SQL server 2005?
Please help me as soon as possible.
Primary ID = BC
Mar 23, 2005A column will be Primary Key. Others are B and C. I want A will contain B and C. I mean B data is X, C data is Y, A will be XY. How can i do this? Can i set in MSSQL or need ASP.NET?
View 1 Replies View RelatedPrimary Key
Dec 1, 1998Heya,
I'm trying to setup a Primary Key on a SQL 6.5 database.
Is there a way to do this? When I hit advanced, it asks for me to select a field for the primary key, but it doesnt list fields to selct from, and I cant type it in.
Thanks for your help,
DTS Is Not Getting The Primary Key
Jul 8, 2004Hi All,
Using DTS i have imported the data from sybase to MS SQL server and all the data and tables were imported correctly.But the primary keys are not marked why is it like this?
This is not a one time job and this is meant to be for the customers also.I cannot ask the customers to mark the primary keys themselves. Is there a way to get the keys also.While doing DTS I have marked all the options correctly.
Please help.
Primary Key
Sep 23, 2004I am setting up some tables where I used to have an identity column as the primary key. I changed it so the primary key is not a char field length of 20.
Is there going to be a big performance hit for this? I didn't like the identity field because every time I referenced a table I had to do a join to get the name of object.
EG:
-- Old way
tbProductionLabour
ID (pk)| Descr | fkCostCode
----------------------
1 | REBAR | 1J
tbTemplateLabour
fkTemplateID | fkLabourID | Manpower | Hours
--------------------------------------------
1 | 1 | 1 | 0.15
-- New way
tbProductionLabour
Labour | fkCostCode
---------------------
REBAR | 1J
tbTemplateLabour
fkTemplateID | fkLabour | Manpower | Hours
-------------------------------------------
1 | REBAR | 1 | 0.15
This is a very basic example, but you get the idea of what I am referring to.
Any thoughts?
Mike
Primary Key
Dec 3, 2004I need to create my own primary key, how do I go about doing that?? In the database I am working in usually has a primary key that looks like this VL0008
the V is for Vendors, thats basically their number. Some of these Vendors need to be licensed and some dont, the ones that are not licensed dont get a number but I am to use that as the Primary/Index key I need to create one for those particual vendors. How can I go about doing that??? I was wanting to make it TL888 something like that.
How To Get Primary Key....plz Help!!!!
Oct 17, 2005i'm having problem to get th primary key from d database....
for your information i'm using java to get the primary key....
this is my code...
rs = stt.executeQuery("sp_columns "+table_db+";");
while(rs.next())
{
out.write(""+rs.getString("COLUMN_NAME"));
out.write(", "+rs.getString("TYPE_NAME"));
out.write(", "+rs.getString("IS_NULLABLE"));
}
rs = stt.executeQuery("sp_foreignkeys @table_name = N'table_db';");
but the problem is....
i get this error message...could anyone tell me what's the problem....
java.sql.SQLException: [Microsoft][ODBC SQL Server Driver][SQL Server]Could not
find server 'table_db' in sysservers. Execute sp_addlinkedserver to add th
e server to sysservers.
how do i solve this problem....
thanx to anyone who can help me...... :D
Primary Key
Oct 18, 2006Please help:
I am creating a table called Bonus:
ProductHeading1
ProductHeading2 (could be null)
ProductHeading3(could be null)
Bonus
Datefrom
DateTo
.... what would be the primary key?! I know it would be DateTo and sumfing...... Since Heading2 and Heading3 could be null, they cannot be PK... and heading1 cannot be a PK because the following three DIFFERENT options could have the same heading1
Option 1) heading1 = "X" heading2 = Null heading3 = Null
Option 2) heading1 = "X" heading2 = "Y" heading3 = Null
Option 3) heading1 = "X" heading2 = "Y" heading3 = "Z"
... but I need a PK to make sure a bonus is not entered twice... I considered added an Id, but them how do I assign a id?! what would i make the id equal to???
Thanks....
Is It Possible To To Have A Primary Key That...
Feb 3, 2008Hi all,
Is it possible to have a primary key for SQL or Oracle or jet to have an alpanumeric beginning?
for example
1st District as a primary key
The statement is:
SELECT itemid FROM MASecurity WHERE userid=%d
Thanks,
Jj :)
Name Of Primary Key
Jan 27, 2004What 's the way to know
the name of the column that is
the primary key of a table
Primary Key
Mar 11, 2004In a recent course on database programming using Microsoft Access 2002. I noticed that the text entitiled New Perspectives Microsoft Access 2002 stated that a primary key could only be used once per table. But If I am not mistaken could one use the select key to select more than one primary key within a table.
View 8 Replies View RelatedPrimary Key
Apr 14, 2008Hi guys,
Is there a method in sql server 2005 to format the primary key so it can be alphanumberic?
Thanks.
Primary Key
May 5, 2008Violation of PRIMARY KEY constraint 'PK_Dunning_TBL'. Cannot insert duplicate key in object 'Dunning_TBL'.
The statement has been terminated.
(0 row(s) affected)
Msg 2627, Level 14, State 1, Procedure GenerateFiles_FST_SP, Line 220
Violation of PRIMARY KEY constraint 'PK_Exceptions_TBL'. Cannot insert duplicate key in object 'Exceptions_TBL'.
The statement has been terminated.
i got this error how can i resolve this?
Last Name-First Name Primary Key?
May 23, 2008Hi,
I am designing a database for containing the info for the employees in the institution. My dilemma:
-Should I use an sql autonumber primary key?
or
-should I merge lastName+FirstName+middleName into one field and use this string as the primary key?
thank you
Primary Key?
Jun 17, 2008I'm new to these forums, and I'm not a database developer, per se, so please forgive me if I make any newb'ish comments.
I have a lookup table called tblCars, that has two columns, cars_id and cars_title. Typically what I do with tables like this is I make cars_id an autonumber, and cars_title the primary key.
The cars_title would contain unique data such as Ford, Chevy, Toyota, etc, which is why I like to make it the primary key (ie - guarantee that it remains unique and no duplicates are ever placed in it).
I would then create an index on cars_id so that I could use it in foreign key constraints.
However, I'm being told by a number of people that it is incorrect to make cars_title the primary key, and that the autonumber field should be the primary key. Yet I am having trouble arriving at a real good reason as to why this is the correct way to do it. I like the warm-fuzzies that I get knowing that no one can accidentally insert a duplicate car title into tblCars because of the primary key constraint.
Thanks in advance for any thoughts or insights on this.