This is the scripts for schema.SQL. It shows error when it gets to the alter table section of the scripts:
DROP TABLE IF EXISTS billing_address;
CREATE TABLE billing_address (
id bigint(20) NOT NULL AUTO_INCREMENT,
billingAddressCity varchar(255),
billingAddressCountry varchar(255),
billingAddressName varchar(255),
billingAddressState varchar(255),
billingAddressStreet1 varchar(255),
billingAddressStreet2 varchar(255),
billingAddressZipCode varchar(255),
order_id bigint (20),
PRIMARY KEY (id)
);
alter table user_role drop constraint if exists FKa68196081fvovjhkek5m97n3y foreign key (role_id) references role (roleid);
alter table user_role add constraint FKa68196081fvovjhkek5m97n3y foreign key (role_id) references role (roleid);
> Caused by: org.h2.jdbc.JdbcSQLException: Syntax error in SQL statement "ALTER TABLE BILLING_ADDRESS DROP CONSTRAINT IF EXISTS FKN9O6NQ40AQJYEBAOFKOLMGV69 FOREIGN[*] KEY (ORDER_ID) REFERENCES USER_ID "; SQL statement:
alter table billing_address drop constraint if exists FKn9o6nq40aqjyebaofkolmgv69 foreign key (order_id) references user_id [42000-196]
The syntax for drop constraint doesn't expect the constraint definition, just the name. So try replacing
alter table billing_address drop constraint if exists FKn9o6nq40aqjyebaofkolmgv69
foreign key (order_id) references user_id ;
with just
alter table billing_address drop constraint if exists FKn9o6nq40aqjyebaofkolmgv69 ;
And similarly for the rest of the following drop statements.
Related
What am I doing wrong? I'm trying to add a foreign key to an existing table
ALTER TABLE orders
ADD CONSTRAINT fk_orders_SalesRep
FOREIGN KEY (snum)
REFERENCES SalesRep(snum);
Table information
create table SalesRep(
snum varchar(5) primary key,
sname varchar(10),
hours Int
)
create table orders(
odId varchar(5) primary key,
itId varchar(5) foreign key(itId) references items(itId)
)
Like Martin said add the column first
ALTER TABLE orders
ADD snum varchar(5);
And then add the fk
ALTER TABLE orders
ADD CONSTRAINT fk_orders_SalesRep
FOREIGN KEY (snum)
REFERENCES SalesRep(snum);
In my database, I have the following code
CREATE TABLE [Users]
(
userID INT NOT NULL IDENTITY(1,1) PRIMARY KEY,
Username VARCHAR(255),
Password VARCHAR(255)
);
CREATE TABLE [Image]
(
ImageID INT NOT NULL IDENTITY(1,1) PRIMARY KEY,
Imagename VARCHAR,
userID INT,
FOREIGN KEY(userID) REFERENCES Users (userID)
);
However, here on stackOverflow and multiple other sites, people suggest writing it like this:
CREATE TABLE [Users]
(
userID INT NOT NULL IDENTITY(1,1) PRIMARY KEY,
Username VARCHAR(255),
Password VARCHAR(255)
);
CREATE TABLE [Image]
(
ImageID INT NOT NULL IDENTITY(1,1) PRIMARY KEY,
Imagename VARCHAR,
userID INT,
CONSTRAINT fk_Users
FOREIGN KEY(userID) REFERENCES Users (userID)
);
I've tried executing both statements, and it seems to do the same..
What am I missing, what's the trick when writing CONSTRAINT fk_Users?
Writing constraint allows you to name the constraint.
In general, you notice this when the constraint is violated. If you have an opportunity to name the constraint, the error message will make more sense.
For instance, this:
The INSERT statement conflicted with the FOREIGN KEY constraint
"fk_image_userId". The conflict occurred in database "rextester",
table "dbo.Users", column 'userID'.
The statement has been terminated.
is clearer than this:
The INSERT statement conflicted with the FOREIGN KEY constraint
"FK__Image__userID__09211CD4". The conflict occurred in database
"rextester", table "dbo.Users", column 'userID'.
The statement has been terminated.
In addition, the constraint name is used in the alter table when you drop or disable the constraint, so having a reasonably named constraint makes that easier.
I have no idea why I get an error when putting the foreing keys in MariaDB
I drop the full database if it exists
drop database if exists proveedoresCarrito;
create database proveedoresCarrito;
use proveedoresCarrito;
And now I'm going to create the tables
CREATE TABLE INVENTARIO (
NUMPIEZA CHAR(16) NOT NULL,
NUMBIN SMALLINT NOT NULL,
CANTDISPONIBLE SMALLINT,
FECHARECUENTO DATE,
PERIODORECUEN SMALLINT,
CANTAJUSTE SMALLINT,
CARTREORD SMALLINT,
PUNTOREORD SMALLINT);
CREATE TABLE LINPED (
NUMPEDIDO SMALLINT NOT NULL,
NUMLINEA SMALLINT NOT NULL,
NUMPIEZA CHAR(16),
PRECIOCOMPRA INTEGER,
CANTPEDIDA SMALLINT,
FECHARECEP DATE,
CANTRECIBIDA SMALLINT);
CREATE TABLE PEDIDO (
NUMPEDIDO SMALLINT NOT NULL,
NUMVEND SMALLINT,
FECHA DATE);
CREATE TABLE PIEZA (
NUMPIEZA CHAR(16) NOT NULL,
NOMPIEZA CHAR(30),
PRECIOVENT INTEGER);
CREATE TABLE PRECIOSUM (
NUMPIEZA CHAR(16) NOT NULL,
NUMVEND SMALLINT NOT NULL,
PRECIOUNIT INTEGER,
DIASSUM SMALLINT,
DESCUENTO SMALLINT);
CREATE TABLE VENDEDOR (
NUMVEND SMALLINT NOT NULL,
NOMVEND CHAR(30),
NOMBRECOMER CHAR(30),
TELEFONO CHAR(15),
CALLE CHAR(30),
CIUDAD CHAR(20),
PROVINCIA CHAR(20),
COD_POSTAL CHAR(5));
create table usuarios(
nombre SMALLINT NOT NULL,
pass CHAR(15)
);
I Set up the primary keys
ALTER TABLE INVENTARIO ADD CONSTRAINT CP_INVENTARIO PRIMARY KEY (NUMBIN);
ALTER TABLE LINPED ADD CONSTRAINT CP_LINPED PRIMARY KEY (NUMPEDIDO, NUMLINEA);
ALTER TABLE PEDIDO ADD CONSTRAINT CP_PEDIDO PRIMARY KEY (NUMPEDIDO);
ALTER TABLE PIEZA ADD CONSTRAINT CP_PIEZA PRIMARY KEY (NUMPIEZA);
ALTER TABLE PRECIOSUM ADD CONSTRAINT CP_PRECIOSUM PRIMARY KEY (NUMPIEZA, NUMVEND);
ALTER TABLE VENDEDOR ADD CONSTRAINT CP_VENDEDOR PRIMARY KEY (NUMVEND);
AND FINALLY i set up the foreign keys
ALTER TABLE INVENTARIO ADD CONSTRAINT CP_INVENTARIO PRIMARY KEY (NUMBIN);
ALTER TABLE LINPED ADD CONSTRAINT CP_LINPED PRIMARY KEY (NUMPEDIDO, NUMLINEA);
ALTER TABLE PEDIDO ADD CONSTRAINT CP_PEDIDO PRIMARY KEY (NUMPEDIDO);
ALTER TABLE PIEZA ADD CONSTRAINT CP_PIEZA PRIMARY KEY (NUMPIEZA);
ALTER TABLE PRECIOSUM ADD CONSTRAINT CP_PRECIOSUM PRIMARY KEY (NUMPIEZA, NUMVEND);
ALTER TABLE VENDEDOR ADD CONSTRAINT CP_VENDEDOR PRIMARY KEY (NUMVEND);
ALTER TABLE usuarios ADD CONSTRAINT CA_VENDEDOR_USUARIOS_NOMBRE FOREIGN KEY (nombre) REFERENCES VENDEDOR(NUMVEND);
ALTER TABLE usuarios ADD CONSTRAINT CA_VENDEDOR_USUARIOS_PASS FOREIGN KEY (pass) REFERENCES VENDEDOR(TELEFONO);
However, all the foreign keys work correctly except for the last two
when i run the sql script i get this error:
Error de SQL (1822): Failed to add the foreign key constaint. Missing index for constraint 'CA_VENDEDOR_USUARIOS_PASS' in the referenced table 'vendedor'
if I drop the last two foreign keys the error disappears
Anyone can give me a solution?
Look closely at your "set up the foreign keys" code. It creates primary keys again (except the two last lines).
Table usuarios seems to have no primary key.
ALTER TABLE usuarios ADD CONSTRAINT CP_usuarios PRIMARY KEY (nombre);
Delete the first 6 lines and keep only these
ALTER TABLE usuarios ADD CONSTRAINT CA_VENDEDOR_USUARIOS_NOMBRE
FOREIGN KEY (nombre)
REFERENCES VENDEDOR(NUMVEND);
ALTER TABLE usuarios ADD CONSTRAINT CA_VENDEDOR_USUARIOS_PASS
FOREIGN KEY (pass)
REFERENCES VENDEDOR(TELEFONO);
Also (and this is what generates your error), you are trying to add a foreign key to a column VENDEDOR(TELEFONO) which is not a primary key nor has a UNIQUE constraint.
According to Microsoft:
A foreign key constraint does not have to be linked only to a primary key constraint in another table; it can also be defined to reference the columns of a UNIQUE constraint in another table.
See: Create Foreign Key Relationships
Add this before creating the foreign keys:
ALTER TABLE VENDEDOR ADD CONSTRAINT UX_telefono UNIQUE (TELEFONO);
A foreign key has to reference always a primary key.
For you to reference the table VENDEDOR you should use the columns that compose its PK. In this example, NUMVEND.
If you need any suggestions on what to do, i'd have to know what are your intentions on this DB structure.
I built a big database with many tables. After that I forgat to add "delete on cascade". How do I add the "delete on casade" on the specific columns I want ?
For example:
create table Users
(
ID char(9) primary key check (ID like replicate('[0-9]',9)),
firstName nvarchar(20) not null,
)
And
create table Applications
(
name nvarchar(20) primary key,
establishDate date not null
)
How do I alter this table-registered to, so that when I delete an app or users it deletes the rows that has this value?
create table RegisteredTo
(
userID char(9) references Users(ID),
ApplicationName nvarchar(20) references Applications(name),
primary key(userID, ApplicationName)
)
I tried something like that - but I got errors.
alter table RegisteredTo
ALTER COLUMN applicationName references Applications(name) ON DELETE CASCADE
nvarchar(20)
You need to add a FOREIGN CONSTRAINT and ON DELETE CASCADE:
ALTER TABLE RegisteredTo
ADD CONSTRAINT FK_RegisteredTo_Users FOREIGN KEY (userID) REFERENCES Users(ID) ON DELETE CASCADE;
ALTER TABLE RegisteredTo
ADD CONSTRAINT FK_RegisteredTo_Applications FOREIGN KEY (ApplicationName) REFERENCES Applications(name) ON DELETE CASCADE;
can't delete the primary and foreign key, it's simple table but i don't why this error
create table student (
s_ID int ,
S_NAMe varchar2 (10),
S_major varchar2(20),
D_ID number (10) ,
Constraint PK_s_ID primary key (s_ID),
constraint FK_D_ID foreign key (D_ID) references dep (D_ID) );
ALTER TABLE student DROP CONSTRAINT PK_s_ID cascade;
alter table student drop constraint FK_D_ID;
ERROR at line 1:
ORA-02443: Cannot drop constraint - nonexistent constraint
You SQL commands looks correct. You can use following command to make sure constraint exists.
SELECT * FROM user_cons_columns WHERE table_name = 'STUDENT'
If it returns no result, that means you either did not create a constraint or already dropped. You may be trying to re-run the same alter command more than once.