Script For Creating Table With Multiple Primary Keys
Feb 1, 2007
Hi,
I am trying to execute following sql script in sql-server 2000 query analyzer
CREATE TABLE user_courses (user_id varchar(30) NOT NULL PRIMARY KEY,
course_id varchar(10) NOT NULL PRIMARY KEY)
Its give's me following error :-
Cannot specify multiple primary key constraint
Hence I am not able to ceate table with multiple primary keys. So can any one tell me how to get this done?.
Secondly, Primary key must be unique i.e duplicate values are not allowed in P.K field. But in this case since I am declaring two fileds as primary keys.
Will it allow me to have following records in the user_courses table?
user_id(P.K) course_id(P.K)
bob CRS235
alice CRS235
Tim CRS235
tom CRS635
So, if we consider both the fields as primary keys together than I am not voilating Uniqueness constraint. But, if I look at course_id alone then I am voilating uniqeness property?
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?
ALTER TABLE [Students] WITH CHECK ADD CONSTRAINT [FK_Students_Schools] FOREIGN KEY([SchoolId]) REFERENCES [Schools] ([SchoolId])
What kind of index would ensure best performance for INSERTs/UPDATEs, so that SQL Server can most efficiently check the FK constraints? Would it be simply:
CREATE INDEX IX_Students_SchlId ON Students (SchoolId) Or CREATE INDEX IX_Students_SchlId ON Students (SchoolId, StudentId)
In other words, what's best practice for adding an index which best supports a Foreign Key constraint?
Can someone tell me what is the best way to check 2 tables lets say tb1 and tb2, to find those customers that are in tb1 but not in tb2 using four fields(cardno,spend,date,refno) as the primary key. Duplicates fields are in tb1
Hi, from the "best practice" perspective, how convenient is to use multiple field primary keys in a table, how convenient is it to replace a multifield pk with an autoincrement field to represent such a table? I tried using a calculated field product of appending the fields that cvompose the primary key, but MySQL for example, does not provide with that functionality, which makes me wonder it doing so in SQL Server is a good practice at all.
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.
I have a database in XML format , with 100+ tables, that I want to import into SQL server but the problem is that I don't have any of the original primary key information. I know that some of the tables had multiple primary keys.
Is there a method or a tool that is capable of determining the primary keys for me??
I don't want to have to figure it out by hand, especially if I have more of these databases in the future.
I have a table fields Register_date, Std_ID, course, version, CourseLearningDays, Batch_Time and Trainer_IDHOw to make Register_date and Batch_Time as primary key in the table.. What are the necessary datatype for these two fields.And one more do we have datatype called date and time in MS SQL Server...
I load values from a TXT file into the temporary table. From there, I figure out which records are new and need to be added to the primary table, and which records are duplicates, and need to a) update the primary table and b) be deleted from the temporary table.Basically, I need to write a SQL statement to grab the records that exist in BOTH tables based upon two primary criteria:
d_id in temporary table = d_id in primary table df_t_v_stock_number in temporary table = v_stock_number in primary table
There are several fields that must be updated if the d_id and v_stock_number match:
We have a SQL Server 6.5 table, with composite Primary Key, having the Duplicate Entry for the Key. I wonder how it got entered there? Now when we are trying to import this table to SQL2K, it's failing with Duplicate row error. Any Help?
I've attempted to identify a primary and foreign key in these two tables, but I am getting a bunch of errors re duplicate keys and column names needing to be unique.Perhaps the primary and foreign key I have identified don't meet the criteria?
CREATE TABLE StockNames ( -- Added Primary key to [stock_symbol] [stock_symbol] VARCHAR(5) NOT NULL CONSTRAINT PK_stock_symbol PRIMARY KEY, [stock_name] VARCHAR(150) NOT NULL, [stock_exchange] VARCHAR(50) NOT NULL,
Pls let me know How I generate script for All primary keys and foreign keys in a table. Thereafter that can be used to add primary keys and foreign keys in another databse with same structure.
Also how I script default and other constraints of a table?
I use the following 3 sets of sql code in SQL Server Management Studio Express (SSMSE) to import the csv data/files to 3 dbo.Tables via CREATE TABLE & BUKL INSERT operations:
-- ImportCSVprojects.sql --
USE ChemDatabase
GO
CREATE TABLE Projects
(
ProjectID int,
ProjectName nvarchar(25),
LabName nvarchar(25)
);
BULK INSERT dbo.Projects
FROM 'c:myfileProjects.csv'
WITH
(
FIELDTERMINATOR = ',',
ROWTERMINATOR = ''
)
GO ======================================= -- ImportCSVsamples.sql --
USE ChemDatabase
GO
CREATE TABLE Samples
(
SampleID int,
SampleName nvarchar(25),
Matrix nvarchar(25),
SampleType nvarchar(25),
ChemGroup nvarchar(25),
ProjectID int
);
BULK INSERT dbo.Samples
FROM 'c:myfileSamples.csv'
WITH
(
FIELDTERMINATOR = ',',
ROWTERMINATOR = ''
)
GO ========================================= -- ImportCSVtestResult.sql --
USE ChemDatabase
GO
CREATE TABLE TestResults
(
AnalyteID int,
AnalyteName nvarchar(25),
Result decimal(9,3),
UnitForConc nvarchar(25),
SampleID int
);
BULK INSERT dbo.TestResults
FROM 'c:myfileLabTests.csv'
WITH
(
FIELDTERMINATOR = ',',
ROWTERMINATOR = ''
)
GO
======================================== The 3 csv files were successfully imported into the ChemDatabase of my SSMSE.
2 questions to ask: (1) How can I designate the Primary and Foreign Keys to these 3 dbo Tables? Should I do this "designate" thing after the 3 dbo Tables are done or during the "Importing" period? (2) How can I set up the relationships among these 3 dbo Tables?
I need to create a new table in our database. This table is not linked into the existing schema in anyway, so i'm not sure if I need a primary key or not. either way, coudl anyone tell me how to create a primary key ni the CREATE TABLE statement. I have tried searching but cannot find the answer.
Hey,I am having some confusion about how to formulate this particularquery.I have 2 tables. Table A has 4 columns say a1,a2,a3,a4 with thecolumns a1,a2,a4 forming the primary key. Table B again has 3 columnswith b1,b2,b3,b4 and like before, b1,b2 and b4 form the primary key.All columns are of the same datatype in both tables. Now I want to getrows from table A which are not present in table B. Whats the best wayof doing this?Thanks--Posted using the http://www.dbforumz.com interface, at author's requestArticles individually checked for conformance to usenet standardsTopic URL: http://www.dbforumz.com/General-Dis...pict235166.htmlVisit Topic URL to contact author (reg. req'd). Report abuse: http://www.dbforumz.com/eform.php?p=815725
I want to partition this table on 5 different coulumns.
year, month. coulumn3, coulumn4 and coulumn5.
How do I do this best?
What is the best way of doing this; is there any best practice on ths?
The obvious thing is to make a partition funktion based on the year and month coulmns, but I also want to partition on coulumn3, coulumn4 and coulumn5.
I am building a DTS Package that is moving data from our webstore (written in house) to a Warehouse Management System(WMS - Turnkey) and I've encountered a problem. both pieces of software have an orders table and an Ordered_Items table, related by the order_ID (makes sense so far). Here is the problem. The primary key on the webstore's Ordered_Items table is a single column (basically an Identity variable), while the primary key on the WMS's Ordered_Items table is a dual column primary key, between the Order_ID and the Order_LineID, so the data should be stored like:
OrderID Order_LineID 1 1 2 1 2 2 2 3 3 1 3 2 4 1
Get the Idea? So I have to create this new Order_LineID column. How can I accomplish this with a SQL statement?
This is a fairly simple question, but what is the easiest way to:create a new numbered column (where value is simply the row number) inan existing table and setting it as a primary key?
This EXECUTES with no error or warning message.However, if I change this to CREATE the PK in an ALTER TABLE statement, I get the (expected by me) error:
==> Msg 8111, Level 16, State 1, Line 17 Cannot define PRIMARY KEY constraint on nullable column in table '#ABC'.
==> Msg 1750, Level 16, State 0, Line 17 Could not create constraint. See previous errors.
(note: As the #ABC table is an actual copy of a few of the columns in a "permanent" table, I will likely change the definition as follows such that the columns are defined to match the names / datatypes / NULLability:
SELECT TOP 0 CAST('01-01-1980' AS DATETIME) AS [ReportRunTime] ,SourceID ,VisitID ,BaseID ,OccurrenceSeqID
As u can see there is two company references in my fact table, and the schema is in snowflake. My customer requirements state that the Contracts' amounts can be aggregated/filtered for/by, ServiceProviderCompany, its city/profession or ClientCompay, its city/profession.
First thing came in to my mind is to dublicate whole dimension structure (one for serviceproviders, one for clients), which i thought that there should be another way around?
"Violation of PRIMARY KEY of restriction 'PK_Approve_Overtime'. The overlapping key cannot be inserted in object 'Dbo.Approve_Overtime'. The statement was ended." can soemone explain to me why i have this kind of error? i have this two tables. approve_overtime table has a primary key id_no and application_input table with a primary key of id_no! all the values from of application_input will be stored also in approve_overtime. sometimes the datas can be stored.sometimes it cannot and produces an error!
Using SQL Svr 7.0. It appears that primary keys are created as nonclustered unique indexes. Is there a configuration setting I can use to make them be created as clustered unique indexes?
If a table has a column defined as Int, Identity(1,1) which is to be used as the primary key, should that index be defined as clustered or non-clustered? In Enterprise manager when you create a PK on a table it defaults to being a clustered index. I am sure the answer depends on the other index requirements and columns in the table but I'd like to see what other ppl think about this.
I have read that SQL Server tables can't have more than one primary key. I know in Access two keys are allowed. Why can't there be two primary keys in a single table in SQL Server 7.
I accidently removed the primary keys from my table by mistake. Is there anyway ,That i can get the PK's back to what is used to be. Need Help pls...... When I try "resetting" the PK I kep getting this error:
'table_name' table - Unable to create index 'PK_tablename'. ODBC error: [Microsoft][ODBC SQL Server Driver][SQL Server]CREATE UNIQUE INDEX terminated because a duplicate key was found for index ID 1. Most significant primary key is '1'. [Microsoft][ODBC SQL Server Driver][SQL Server]Could not create constraint. See previous errors. [Microsoft][ODBC SQL Server Driver][SQL Server]Warning: The table 'tDetail' has been created but its maximum row size (12521) exceeds the maximum number of bytes per row (8060). INSERT or UPDATE of a row in this table will fail if the resulting row length exceeds 8060 bytes. [Microsoft][ODBC SQL Server Driver][SQL Server]The statement has been terminated.
In access you can have two fields that are primary keys with one or the other repeating as long as the combination is not repeated. i.e. key1 key2 200410 12345 200410 12346 200410 12588 etc for all 200410 there can not be a repeat of any value of key 2
is there a way to have this dual key in MSSQL :confused:
I have declared a table with a single column to be a Primary key. If I write 2 records, the first comprsing "A" and the second "a" then I get an exception about violating the uniqueness of the key. Is there a way that I can define the key to be case sensitive.
I have two tables with similar primary keys, table a and table b, and I want to find out all the key values that are disimilar between the tables. Can this be done with a select? if so what would it be.
I am not entirly sure what a forigen key is, is it a unique ID which is the same as the primary key? If adding a foreign key to a table that already has data, will it update each row with a unique ID or will it only create a unique ID on newly inserted records (for the foreign key)? If the foreign key is the same as the primary key then why do we need to even add a foreign key at all?For example a table like: Table Name : Customers--CustomerID uniqueidentity (primary Key)--FirstName nchar Table Name : Orders --OrderID int--CustomerID int Obviuously CustomerID are going to be the same in both tables, so why would you need to add a foreign key on 'CustomerID' to the 'Order' table, can't SQL match the customerID in each table any way? Cheers