SQL Server 2008 - Create a Join Table - sql-server

I'm having issues creating a simple join table (associative table, etc. whatever your flavor is).
These are test tables, so there is not much to them.
First table is
CREATE TABLE dbo.CareerField(
CareerFieldID int IDENTITY(1,1) NOT NULL,
CareerFieldName varchar(100) NOT NULL
)
Second Table is
CREATE TABLE dbo.Cluster(
ClusterID int IDENTITY(1,1) NOT NULL,
ClusterName varchar(100) NOT NULL
)
Third table (join table) to create a many-to-many relationship is
CREATE TABLE dbo.CareerField_Cluster(
CareerFieldID int NOT NULL,
ClusterID int NOT NULL
)
I am trying to set foreign keys in this third table using the following
ALTER TABLE dbo.CareerField_Cluster
ADD CONSTRAINT FK_CareerField_Cluster_CareerFieldID
FOREIGN KEY(CareerFieldID) REFERENCES dbo.CareerField(CareerFieldID)
ALTER TABLE dbo.CareerField_Cluster
ADD CONSTRAINT FK_CareerField_Cluster_ClusterID
FOREIGN KEY(ClusterID) REFERENCES dbo.Cluster(ClusterID)
However, I keep getting an error of
Msg 1776, Level 16, State 0, Line 1
There are no primary or candidate keys in the referenced table 'dbo.CareerField' that match the referencing column list in the foreign key 'FK_CareerField_Cluster_CareerFieldID'.
Msg 1750, Level 16, State 0, Line 1
Could not create constraint. See previous errors.
I try setting both fields as a primary key, but it will not allow me to select a separate table when creating the key - I can't select CareerFieldID to reference CareerField Table and then ClusterID to reference Cluster Table.
I've not had this issue with MySQL and I am new to SQL Server. Any help is much appreciated.

For each of your tables CareerField and Cluster, ensure you have a PK designated via the CONSTRAINT directive.
CREATE TABLE [dbo].[CareerField]
(
[CareerFieldID] [int] IDENTITY(1,1) NOT NULL,
[CareerFieldName] [varchar](100) NOT NULL,
CONSTRAINT [PK_Career] PRIMARY KEY CLUSTERED
(
[CareerFieldID] ASC
)
)

Related

Delete constraint and table

I created table named as Dates and also I inserted value from other table. You can see how look lines of code below
--Create table
CREATE TABLE [dimension].[Dates](
[Year] [int] NOT NULL,
[Month] [tinyint] NOT NULL,
[MonthName] [varchar](10) NOT NULL,
[Quarter] [tinyint] NOT NULL,
[MMYYYY] [char](6) NOT NULL
CONSTRAINT [PK_Dates] PRIMARY KEY CLUSTERED (MMYYYY ASC))
--Insert data
INSERT INTO [dimension].[Dates] ([Year],[Month],[MonthName],[MonthName], [MMYYYY])
SELECT DISTINCT [Year],[Month],[MonthName]0,[MonthName], [MMYYYY]
FROM [dimension].[Date]
Additionally I assign foreign key on FACT.FactTable with primary key of this table with this line of code.
ALTER TABLE FACT.FactTable
ADD
FOREIGN KEY (MMYYYY) REFERENCES [DIMENSION].[Dates] (MMYYYY)
So far so good. But know I want to delete this table and make again with additional columns. In order to do this I use this command below but can't work.
ALTER TABLE DIMENSION.Dates
DROP CONSTRAINT [PK_Dates]
Msg 3725, Level 16, State 0, Line 183
The constraint 'PK_Dates' is being referenced by table 'FactTable', foreign key constraint 'FK__FactTable__MMYYY__33F4B129'.
Msg 3727, Level 16, State 0, Line 183
Could not drop constraint. See previous errors.
Because this line don't work for me I can use command drop table to delete this table, so can anybody help me how to solve this issue?
You cannot DROP table if there are other tables that are referencing to your dimension.Dates table or in other case you cannot DELETE data if there are other tables which data are referenced to data in table FACT.FactTable. You should first drop CONSTRAINT and then drop table.
ALTER TABLE FACT.FactTable DROP CONSTRAINT FK__FactTable__MMYYY__33F4B129;
Once the constraint is dropped and you don't have any other references to dimention.Dates you can execute the following statement:
DROP TABLE dimension.Dates;
The error message says the FACT.FactTable's foreign depends on PK_Dates. Drop that first. It doesn't look like you can modify it from a quick reading of the documentation.

Unable to add a constraint foreign key to a table from an already created table in SQL server management studio 18. Can someone help me?

I'm creating a database for my assignment. I had to create 2 tables namely Customer and Job through the "New Query" option in SQL server. After creating both of them, I wanted to add Job_ID (A primary key) from Job table as a foreign key to the Customer table. As I have already created the Customer table, The only option I had was to ALTER the customer table. But after altering, I seemed to get this unusual error.
Msg 1769, Level 16, State 1, Line 1
Foreign key 'Job_ID' references invalid column 'Job_ID' in referencing table 'CUSTOMER'.
Msg 1750, Level 16, State 0, Line 1
Could not create constraint or index. See previous errors.
I can provide you with any more info if necessary.
CREATE TABLE CUSTOMER
(Customer_ID INT NOT NULL PRIMARY KEY,
Customer_Name VARCHAR(15) NOT NULL,
Gender CHAR(1),
Customer_Type VARCHAR(12) NOT NULL,
Addresss VARCHAR(20) NOT NULL,
Telephone_No CHAR(10) NOT NULL);
CREATE TABLE JOB
(Job_ID INT NOT NULL PRIMARY KEY,
Pickup_location VARCHAR (10) NOT NULL,
Destination VARCHAR (10) NOT NULL,
Customer_ID INT FOREIGN KEY REFERENCES CUSTOMER(Customer_ID));
ALTER TABLE CUSTOMER
ADD FOREIGN KEY (Job_ID) REFERENCES JOB(Job_ID);
This looks like the same issue as described here.
When you try to create your foreign key:
ALTER TABLE CUSTOMER
ADD FOREIGN KEY (Job_ID) REFERENCES JOB(Job_ID);
You are saying that you want to use the field Job_ID from the table CUSTOMER:
ALTER TABLE CUSTOMER ADD FOREIGN KEY (Job_ID)
and that the values in this field should match values in the Job_ID column from the table JOB:
REFERENCES JOB(Job_ID);
The problem is that your CUSTOMER table doesn't have a Job_ID column, based on its definition:
CREATE TABLE CUSTOMER
(Customer_ID INT NOT NULL PRIMARY KEY,
Customer_Name VARCHAR(15) NOT NULL,
Gender CHAR(1),
Customer_Type VARCHAR(12) NOT NULL,
Addresss VARCHAR(20) NOT NULL,
Telephone_No CHAR(10) NOT NULL);
The fields in the CUSTOMER table are Customer_ID,Customer_Name,Gender,Customer_Type,Addresss and Telephone_No.
So you either need to add a Job_ID column to the CUSTOMER table, or specify a different field to use in your ALTER TABLE statement - one which does exist in the CUSTOMER table.
More information on ALTER TABLE and ADD FOREIGN KEY specifically can be found here.

SQL Relation MORE on MORE

I have a question about this relation betweed SpelerTeam and Toernooi, i get a error, can someone help me with it all the other relations do work:
Msg 1776, Level 16, State 0, Line 2 There are no primary or candidate
keys in the referenced table 'SpelerTeam' that match the referencing
column list in the foreign key 'FK__Toernooi__team__1A14E395'. Msg
1750, Level 16, State 0, Line 2 Could not create constraint. See
previous errors.
CREATE TABLE dbo.LoginGegevens
(
Username varchar(25) NOT NULL,
Wachtwoord varchar(25) NOT NULL,
LoginDatum date NOT NULL,
)
CREATE TABLE dbo.NawGegevensKind
(
KindSpeler varchar(25) NOT NULL,
NawKind varchar(50) NOT NULL,
)
CREATE TABLE dbo.NawGegevensProfspeler
(
Profspeler varchar(25) NOT NULL,
NawProfspeler varchar(50) NOT NULL,
)
CREATE TABLE dbo.SpelerTeam
(
Team int NOT NULL,
Kindspeler varchar(25) NOT NULL,
Profspeler varchar(25) NOT NULL,
)
CREATE TABLE dbo.Toernooi
(
team int NOT NULL,
score int NOT NULL,
games int NOT NULL,
rondes int NOT NULL,
)
-- primary keys
ALTER TABLE LoginGegevens
ADD primary KEY (Username)
ALTER TABLE NawGegevensKind
ADD primary KEY (KindSpeler)
ALTER TABLE NawGegevensProfspeler
ADD primary KEY (ProfSpeler)
ALTER TABLE SpelerTeam
ADD primary KEY (Team,KindSpeler,ProfSpeler)
ALTER TABLE Toernooi
ADD primary KEY (Team,Rondes,Games)
-- relation
ALTER TABLE SpelerTeam
ADD FOREIGN KEY (Kindspeler)
REFERENCES NawGegevensKind(Kindspeler);
ALTER TABLE SpelerTeam
ADD FOREIGN KEY (Profspeler)
REFERENCES NawGegevensProfspeler(Profspeler);
ALTER TABLE Toernooi
ADD FOREIGN KEY (Team)
REFERENCES SpelerTeam(Team);
The Primary Key of SpelerTeam is Team,KindSpeler,ProfSpeler.
That means that any foreign key that references that table has to reference all three of those columns. You can't create a foreign key that uses only team.
You need an index on a colum so that it can be referenced as a foreign key efficiently. Add an index on SpelerTeam.Team and on all other columns with the same problem. Try CREATE INDEX IX_SpelerTeam_Team_Team ON SpelerTeam (Team);
Add below after all tables have been created:
CREATE UNIQUE NONCLUSTERED INDEX IX_SpelerTeam_Team
ON dbo.SpelerTeam (Team);
GO
As it was pointed in another answer you cannot reference to non unique column, to make column unique you can make this column primary key or create index for this column.
It is not enough that your "Team" column is part of composite key.

SQL Server & Visual Studio - Insert Data in tables doesn't work

I want to insert my tables from my SQL Server Management Studio code with data via Visual Studio.
But it doesn't work. The ID of my table doesn't get a value automatically (but I have command it with identity(1,1)) and an error appears that it stands in conflict with a foreign-key-constraint.
create table [ProduktZahlungFENutzer]
(
ID int PRIMARY KEY IDENTITY(1,1) NOT NULL,
Endpreis decimal(3, 2)
);
CREATE TABLE [FHAngehörige]
(
FHAngehörigeID INT NOT NULL IDENTITY(1,1)
PRIMARY KEY Constraint fhA_feN
REFERENCES FENutzer(FENutzerID),
Name VARCHAR(50) NOT NULL,
Fachbereich INT NOT NULL,
Email VARCHAR(50) NOT NULL UNIQUE
)
CREATE TABLE [FENutzer]
(
FENutzerID INT IDENTITY(1,1) NOT NULL
PRIMARY KEY constraint t_nutzer
references ProduktZahlungFENutzer(ID),
Aktiv INT NOT NULL,
LetzterLogin datetime NOT NULL DEFAULT GETDATE(),
BENutzerID int NOT NULL
constraint FENutzer_BENutzer
foreign key references BENutzer(BENutzerID),
auth_id int not null
constraint FENutzer_auth
foreign key references auth2(id)
)
Please help
You have established a reference
FHAngehörigeID INT NOT NULL IDENTITY(1,1) PRIMARY KEY Constraint fhA_feN
REFERENCES FENutzer(FENutzerID),
This means that you need a record in your table FENutzer.FENutzerID that match FHAngehörigeID, in this case you cannot use IDENTITY
Your construction makes no sense - this way, you're creating two tables that depend on each other, at the primary key level - so you would have to have an existing entry in FENutzer in order to insert a new row into FHAngehörige, and this at the same time is only possible if you already have an existing row in FHAngehörige to insert the row in FEnutzer.....
You need to clean this up:
both tables need a primary key and the int identity(1,1) is a very good choice
one of the tables must reference the other, but with a normal foreign key attribute - not on the primary key.....
Since you've not given any indication as to which of the tables is the "main" table and which the "child/auxiliary" table, I'm just picking one over the other - so your table structure should be something like:
CREATE TABLE dbo.FHAngehoerige
(
FHAngehoerigeID INT NOT NULL IDENTITY(1,1)
CONSTRAINT PK_FHAngehoerige PRIMARY KEY CLUSTERED,
Name VARCHAR(50) NOT NULL,
Fachbereich INT NOT NULL,
Email VARCHAR(50) NOT NULL UNIQUE
)
CREATE TABLE dbo.FENutzer
(
-- define the PK for the table
FENutzerID INT IDENTITY(1,1) NOT NULL
CONSTRAINT PK_FENutzer PRIMARY KEY CLUSTERED,
-- define the **foreign key** to the main table
FHAngehoerigeID INT NOT NULL
CONSTRAINT FK_FENutzer_FHAngehoerige
FOREIGN KEY REFERENCES dbo.FHAngehoerige(FHAngehoerigeID),
Aktiv INT NOT NULL,
LetzterLogin datetime NOT NULL DEFAULT GETDATE(),
BENutzerID int NOT NULL
constraint FENutzer_BENutzer
foreign key references BENutzer(BENutzerID),
auth_id int not null
constraint FENutzer_auth
foreign key references auth2(id)
)
Also: I would strongly recommend (from my own personal, bad experience) to AVOID any special characters like umlauts or accents or anything like that in table and column names.....

Error upon creating tables in sqlplus

I'm new to sqlplus and was trying to run a sql script that creates a few tables, but once I try to run it, it gives me an error saying that the table or view doesnt exist and I dont know how to fix this error.
My script is:
drop table Borrower;
create table Borrower (
bid char(100) not null,
password char(100) not null,
name char(100) null,
address char(100) null,
phone char(100) null,
emailAddress char(100) null,
sinOrStNo char(100) null,
expiryDate date null,
--type ENUM('student','faculty','staff'),
type char(100) not null,
--CONSTRAINT Btype_check CHECK (type IN ('student','faculty','staff')),
FOREIGN KEY (type) references BorrowerType(type),
PRIMARY KEY (bid));
grant select on Borrower to public;
"unique/primary keys in table referenced by foreign keys "
Data integrity is crucial to a properly run database so Oracle will not let us drop a table if its primary key is referenced by another table's foreign key. So it hurls ORA-02449.
So, given this set up:
create table t_parent (
id number not null
, constraint tp_pk primary key (id)
);
create table t_child (
id number not null
, p_id number not null
, constraint tc_pk primary key (id)
, constraint tc_tp_fk foreign key (p_id)
references t_parent (id)
);
There are three ways to drop table t_parent.
run drop table t_child first: no child table, no foreign key.
Remove the blocking foreign key: alter table t_child drop constraint tc_pc_fk.
A variant on the previous one, let the database figure out the foreign keys:
drop table t_parent cascade constraints.
The first option is the most proper, because it leaves the database in a valid state (no tables, no possibility of data integrity corruption). The valid use for the third approach is a script which razes all the tables from a schema: it's easy to generate such a script from the data dictionary.
The order that you drop or create tables are important because if you have foreign keys referencing another table, you cant delete that table before deleting your own table.
In this example, the Borrower table has to be dropped before the BorrowerType table.

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