I have an entity within Oracle's SQL:
and I'm wondering, what does "UF" represent? I've written the SQL code but I do not know how to represent the "UF" attribute as a constraint.
CREATE TABLE entry (
entryno NUMBER(4) NOT NULL,
carndate DATE NOT NULL,
entrystarttime DATE NOT NULL,
entryfinishtime DATE NOT NULL,
entryplace NUMBER(4) NOT NULL,
charname VARCHAR2(30) NOT NULL,
compno NUMBER(4) NOT NULL,
eventypecode CHAR(3) NOT NULL,
teamname VARCHAR2(30) NOT NULL
);
ALTER TABLE entry ADD CONSTRAINT entry_pk PRIMARY KEY ( entryno,
carndate );
ALTER TABLE entry
ADD CONSTRAINT entry_charity_fk FOREIGN KEY ( charname )
REFERENCES charity ( charname );
ALTER TABLE entry
ADD CONSTRAINT entry_carnival_fk FOREIGN KEY ( carndate )
REFERENCES carnival ( carndate );
ALTER TABLE entry #
ADD CONSTRAINT entry_competitor_fk FOREIGN KEY ( compno )
REFERENCES competitor ( compno );
ALTER TABLE entry #
ADD CONSTRAINT entry_event_fk FOREIGN KEY ( carndate, eventypecode )
REFERENCES evenet ( carndate, eventypecode );
ALTER TABLE entry
ADD CONSTRAINT entry_team_fk FOREIGN KEY ( teamname, carndate )
REFERENCES team ( teamname,carndate );
ALTER TABLE entry
ADD CONSTRAINT ... ("UF")
The UF is actually two flags.
As you've recognised the F means the column is a foreign key. The U stands for Unique. Those columns form part of the compound unique key:
ALTER TABLE entry ADD CONSTRAINT entry_carnival_un UNIQUE
( carndate, compno, eventypecode );
carndate is also part of the compound primary key so really it should be flagged PFU but I guess the modelling tool didn't allow for three flags.
Related
I am trying to create some tables in pgadmim.
Although in both tables tb_discipline and tb_round the discipline_id is the primary key I get the error:
there is no unique constraint matching given keys for the referenced table
"tb_round"
Adding the full code:
CREATE TABLE tb_discipline (
discipline_id INT NOT NULL,
name CHARACTER VARYING(50) NOT NULL,
inventor CHARACTER VARYING(50) NOT NULL,
type CHARACTER VARYING(10) NOT NULL,
object_type CHARACTER(20) DEFAULT NULL,
CONSTRAINT PK_tb_discipline PRIMARY KEY(discipline_id)
);
------------------------------------------------------------------------------------------------
--
-- Create table tb_athlete
--
------------------------------------------------------------------------------------------------
CREATE TABLE tb_athlete (
athlete_id CHARACTER(7) NOT NULL,
name CHARACTER VARYING(50) NOT NULL,
country CHARACTER(3) NOT NULL,
substitute_id CHARACTER (7),
CONSTRAINT PK_tb_athlete PRIMARY KEY(athlete_id),
CONSTRAINT FK_athlete_substitute FOREIGN KEY (substitute_id) REFERENCES tb_athlete(athlete_id)
);
------------------------------------------------------------------------------------------------
--
-- Create table tb_play
--
------------------------------------------------------------------------------------------------
CREATE TABLE tb_play (
athlete_id CHARACTER(7) NOT NULL,
discipline_id INT NOT NULL,
CONSTRAINT FK_play_athlete FOREIGN KEY (athlete_id) REFERENCES tb_athlete(athlete_id),
CONSTRAINT FK_play_discipline FOREIGN KEY (discipline_id) REFERENCES tb_discipline(discipline_id)
);
------------------------------------------------------------------------------------------------
--
-- Create table tb_round
--
------------------------------------------------------------------------------------------------
CREATE TABLE tb_round (
round_number INT NOT NULL,
discipline_id INT NOT NULL,
CONSTRAINT PK_tb_round PRIMARY KEY(round_number, discipline_id),
CONSTRAINT FK_round_discipline FOREIGN KEY (discipline_id) REFERENCES tb_discipline(discipline_id)
);
------------------------------------------------------------------------------------------------
--
-- Create table tb_register
--
------------------------------------------------------------------------------------------------
CREATE TABLE tb_register (
athlete_id CHARACTER(7) NOT NULL,
round_number INT NOT NULL,
discipline_id INT NOT NULL UNIQUE,
register_date DATE NOT NULL DEFAULT CURRENT_DATE,
register_position INT,
register_time TIME,
register_measure REAL,
CONSTRAINT PK_tb_register PRIMARY KEY(athlete_id,round_number,discipline_id),
CONSTRAINT FK_register_athlete FOREIGN KEY (athlete_id) REFERENCES tb_athlete(athlete_id),
CONSTRAINT FK_register_round_discipline FOREIGN KEY (discipline_id) REFERENCES tb_round(discipline_id),
CONSTRAINT FK_register_round_number FOREIGN KEY (round_number) REFERENCES tb_round(round_number)
);
Any idea how can I solve this?
You have two foreign keys in tb_register referencing round but only part of its key. Make that one referencing the complete key.
CREATE TABLE tb_register
(...
CONSTRAINT fk_register_round_number_discipline_id
FOREIGN KEY (round_number,
discipline_id)
REFERENCES tb_round
(round_number,
discipline_id)
...);
So I have two table with id_pastille and I want to create a trigger that each time that one id_pastille is deleted every table that has the id_pastille is deleted as well.
CREATE TABLE tp1_trajet
(
id_trajet int NOT NULL,
longitude double precision NOT NULL,
latitude double precision NOT NULL,
"date" timestamp NOT NULL,
id_pastille int NOT NULL,
CONSTRAINT PK_zone_geographique PRIMARY KEY ( id_trajet ),
CONSTRAINT FK_ FOREIGN KEY ( id_pastille ) REFERENCES tp1_pastille ( id_pastille )
and let say this table
CREATE TABLE tp1_compte
(
id_compte int NOT NULL,
date_achat date NOT NULL,
id_pastille int NOT NULL,
id_usager int NOT NULL,
probabilite_malade double precision NULL,
CONSTRAINT PK_compte PRIMARY KEY ( id_compte ),
CONSTRAINT UQ_compte_id_pastille UNIQUE ( id_pastille ),
CONSTRAINT UQ_compte_id_usager UNIQUE ( id_usager ),
CONSTRAINT FK_compte_id_pastille FOREIGN KEY ( id_pastille ) REFERENCES tp1_pastille ( id_pastille ),
CONSTRAINT FK_compte_id_usager FOREIGN KEY ( id_usager ) REFERENCES tp1_usager ( id_usager )
);
I came up with this so far :
CREATE FUNCTION Delete_pastille() RETURNS trigger
AS $DeleteCustomerWithOrders$
BEGIN
DELETE FROM tp1_bulle,
tp1_compte,
tp1_pastille,
tp1_signes_vitaux,
tp1_usager,
tp1_transaction,
tp1_trajet
WHERE id_pastille = OLD."Id";
RETURN OLD;
END;
$DeleteCustomerWithOrders$
LANGUAGE plpgsql;
You can only delete from a single table in a DELETE statement. Try using several statements.
The best solution might be to define foreign key constraints on all but one of these columns that point to the table that contains the original copy (pastille?). If the foreign key is defined with ON DELETE CASCADE, deleting the original will automatically delete all the dependent rows.
alter table tp1_trajet
drop constraint fK_,
add constraint fK_
foreign key (ID_pastille)
references tp1_pastille (ID_pastille)
on delete cascade;
alter table tp1_compte
drop constraint FK_compte_id_pastille,
add constraint FK_compte_id_pastille
foreign key (ID_pastille)
references tp1_pastille (ID_pastille)
on delete cascade;
I'm trying to created a table, and give as a primary key, the 3 attributes, which it have.
The code is below:
CREATE TABLE compra
(
dni_cli VARCHAR2(50),
cod_prod NUMBER(10) NOT NULL,
cantidad NUMBER (10),
CONSTRAINT pk_compra PRIMARY KEY (dni_cli, cod_prod, cantidad);
CONSTRAINT pelicula_codigo_prod_fg FOREIGN KEY (cod_prod) REFERENCES producto(cod_prod),
CONSTRAINT pelicula_codigo_cli_fg FOREIGN KEY (dni_cli) REFERENCES cliente(dni)
);
I also tried to create the table first, and then, add the constraint in order to create the combined PRIMARY KEY with the alter table, but is doesn't work.
The code is this:
ALTER TABLE CONSTRAINT pk_compra PRIMARY KEY (dni_cli, cod_prod, cantidad);
If the primary key already exists you need to drop the key:
ALTER TABLE compra drop constraint pk_compra;
then add the key:
ALTER TABLE compra add constraint pk_compra primary key (city_id, buildtime, time);
If the primary key does not exist in the table then just use the second command line.
Also as #stickybit noted your table has an error. This is the code without an error:
CREATE TABLE compra (
dni_cli VARCHAR2(50),
cod_prod NUMBER(10) NOT NULL,
cantidad NUMBER (10),
CONSTRAINT pk_compra PRIMARY KEY (dni_cli,cod_prod,cantidad), --<<change here
CONSTRAINT pelicula_codigo_prod_fg FOREIGN KEY (cod_prod) REFERENCES producto(cod_prod),
CONSTRAINT pelicula_codigo_cli_fg FOREIGN KEY (dni_cli) REFERENCES cliente(dni));
I'm trying to turn the Logical Model of my Database into a DDL script, but I don't know how to fix this error in the DDL script or Data Modeller:-- ERROR: FK name length exceeds maximum allowed length(30)
It seems to be based on my junction-table's Primary Key, which is made up from two Foreign Keys from the two neighboring tables.
I have tried changing the names of the Primary Keys in the neighboring tables, but when I try to generate a NEW DDL script with Data Modeler, it still generates the old script.
Here's the sections of code that create the 3 tables and link them together:
CREATE TABLE items (
item_no NUMBER (8) NOT NULL,
"year" DATE,
price NUMBER (20,2)
);
ALTER TABLE items ADD CONSTRAINT items_pk PRIMARY KEY ( item_no );
CREATE TABLE purchase_order (
order_no NUMBER(8) NOT NULL,
quantity INTEGER,
item_description VARCHAR2(200),
unit_price NUMBER(20,2),
total NUMBER(20,2),
order_date DATE,
sales_person_code VARCHAR2(5) NOT NULL,
supplier_id NUMBER(3) NOT NULL
);
ALTER TABLE purchase_order ADD CONSTRAINT purchase_order_pk PRIMARY KEY ( order_no );
CREATE TABLE purchase_order_items (
purchase_order_order_no NUMBER(8) NOT NULL,
items_item_no NUMBER(8) NOT NULL
);
ALTER TABLE purchase_order_items ADD CONSTRAINT purchase_order_items_pk PRIMARY KEY ( items_item_no,
purchase_order_order_no );
ALTER TABLE purchase_order_items
ADD CONSTRAINT purchase_order_items_items_fk FOREIGN KEY ( items_item_no )
REFERENCES items ( item_no );
-- ERROR: FK name length exceeds maximum allowed length(30)
ALTER TABLE purchase_order_items
ADD CONSTRAINT purchase_order_items_purchase_order_fk FOREIGN KEY ( purchase_order_order_no )
REFERENCES purchase_order ( order_no );
ALTER TABLE purchase_order
ADD CONSTRAINT purchase_order_sales_person_fk FOREIGN KEY ( sales_person_code )
REFERENCES sales_person ( code );
ALTER TABLE purchase_order
ADD CONSTRAINT purchase_order_supplier_fk FOREIGN KEY ( supplier_id )
REFERENCES supplier ( id );
So I'm not sure exactly what FK name length is too long and what I need to change in the script to fix this error.
Oracle limits identifiers to 30 characters, so
purchase_order_items_purchase_order_fk needs to be shorted. Perhaps to something like poi_purchase_porder_fk.
I have three tables that are linked together
My script:
-- Ticket --
CREATE TABLE public.ticket (
id bigint NOT NULL,
libelle character varying(255) NOT NULL,
description character varying(255) NOT NULL,
status character varying(255) NOT NULL,
date_creation timestamp NOT NULL,
date_modification timestamp NOT NULL,
user_createur_id bigint,
referent_realisateur_id bigint,
CONSTRAINT pk_ticket PRIMARY KEY (id)
);
-- Ticket_Avance TABLE --
CREATE TABLE public.ticket_avance (
id bigint NOT NULL,
date_livraison_souhaite timestamp NOT NULL,
date_engagement_livraison timestamp NOT NULL,
referent_demandeur_id bigint
);
ALTER TABLE public.ticket_avance ADD CONSTRAINT "fk_ticket_ticketAvance" FOREIGN KEY (id)
REFERENCES public.ticket (id) MATCH SIMPLE
ON DELETE NO ACTION ON UPDATE NO ACTION;
-- Demande_Travaux TABLE --
DROP TABLE IF EXISTS public.demande_travaux CASCADE;
CREATE TABLE public.demande_travaux (
id bigint NOT NULL,
contrat_id bigint
);
ALTER TABLE public.demande_travaux ADD CONSTRAINT "fk_ticketAvance_DDT" FOREIGN KEY (id)
REFERENCES public.ticket_avance (id) MATCH FULL
ON DELETE NO ACTION ON UPDATE NO ACTION;
I have this error on the demand_travaux creation
SQL Error [42830]: ERROR: there is no unique constraint matching given keys for referenced table "ticket_avance"
ERROR: there is no unique constraint matching given keys for referenced table "ticket_avance"
ERROR: there is no unique constraint matching given keys for referenced table "ticket_avance"
You have forgotten to declare column ID in table ticket_avance as primary key.
Please use the following SQL:
-- Ticket_Avance TABLE --
CREATE TABLE public.ticket_avance (
id bigint NOT NULL,
date_livraison_souhaite timestamp NOT NULL,
date_engagement_livraison timestamp NOT NULL,
referent_demandeur_id bigint,
CONSTRAINT pk_avance PRIMARY KEY (id) --- add this
);
you need add constraint in Ticket_Avance table because you provide reference this id to demande_travaux
-- Ticket_Avance TABLE --
CREATE TABLE ticket_avance (
id bigint NOT NULL,
date_livraison_souhaite timestamp NOT NULL,
date_engagement_livraison timestamp NOT NULL,
referent_demandeur_id bigint,
CONSTRAINT pk_ticket_avance PRIMARY KEY (id) //constraint that you need
);
ALTER TABLE demande_travaux ADD CONSTRAINT "fk_ticketAvance_DDT" FOREIGN KEY (id)
REFERENCES ticket_avance (id) MATCH FULL
ON DELETE NO ACTION ON UPDATE NO ACTION;
here is the demo link of your full query
A foreign key constraint has to target a primary key or unique constraint. The database has to be able to identify a single row in the "parent" table.
You could add primary key constraints:
ALTER TABLE public.ticket_avance ADD PRIMARY KEY (id);
In addition, you should have an index on the column on which the foreign key is defined, particularly if you plan to delete parent rows. With the primary key above, you have such an index on id, but you also should have one on demande_travaux.
The simplest way is to define id as primary key there too:
ALTER TABLE public.demande_travaux ADD PRIMARY KEY (id);