Consider the table which contains unique Key and Primary Key .the tables already contains data.If i added any rows to the table i received an error (ORA - 0001) which is due to the duplicate value is added to the Primary Key or Unique Key .Here i am not able to identify whether the error is due to the addition of duplicate value to the Primary Key or Unique Key.Can anyone suggest me how to identify this?
The format of the ORA-00001 message is:
ORA-00001: unique constraint violated (string.string)
where string.string is schema.constraint_name. This is why it is good practice to give our constraints helpful names.
create table t23
( id number not null
, col1 varchar2(30)
, col2 date
, constraint t23_pk primary key (id)
, constraint t23_uk unique (col1)
)
/
The error displays the constraint that was violated .
The message shd look like:
ORA-00001: unique constraint
(string.string) violated
where (string.string) will be the name of the constraints
Related
I have this table and i added a check to the column duree
with this condition alter table operation modify Duree integer check(Duree>=2);
but in the homework it's specified that it needs to be like (duree>=44) isntead
how this be fixed.
create table Operation (
CodeOP varchar(20) not null ,
Duree integer ,
Chef integer ,
DateDeb Date ,
Budget float ,
CodeS varchar (20),
constraint pk_operation primary key (CodeOP),
constraint fk_operation foreign key(CodeS)REFERENCES Service(CodeS) on delete set null
i tried alter table operation modify Duree integer check(Duree>=44);
but i'm getting this message :
ERROR at line 1: ORA-02293: cannot validate (TPBDD2.SYS_C008292) - check constraint violated
This question already has an answer here:
ORA-02256: referencing foreign key
(1 answer)
Closed last year.
CREATE TABLE Goft_ForeEver_cus(
customer_Id VARCHAR(10),
first_Name VARCHAR2(20) CONSTRAINT sys_cus_fName_nn NOT NULL,
last_Name VARCHAR2(20) CONSTRAINT sys_cus_lName_nn NOT NULL,
girt_Card_Amount NUMBER(5,2) CONSTRAINT sys_cus_gca_nn NOT NULL,
email VARCHAR2(30) CONSTRAINT sys_cus_email_ck CHECK (email ='%[^a-z,0-9,#,.,_,-]%' ) CONSTRAINT sys_cus_email_nn NOT NULL,
CONSTRAINT sys_cus_pk PRIMARY KEY(customer_Id)
);
ALTER TABLE Goft_ForeEver_cus
ADD CONSTRAINT sys_cus_email_UK UNIQUE (email);
CREATE TABLE Goft_ForeEver_Course_Info(
course_Name VARCHAR2(20),
city VARCHAR2(30) CONSTRAINT sys_courtInf_city_nn NOT NULL,
prov VARCHAR2(20) CONSTRAINT sys_courtInf_prov_nn NOT NULL,
postal_Code VARCHAR2(10) CONSTRAINT sys_courtInf_posC_nn NOT NULL,
star_rating NUMBER(1,1),
discript VARCHAR2(200) CONSTRAINT sys_courtInf_descript_uk UNIQUE,
year_Build DATE CONSTRAINT sys_courtInf_date_nn NOT NULL,
court_length Number(5,2)
CONSTRAINT sys_courtInf_courtL_ck CHECK( court_length = 'YARD')
CONSTRAINT sys_courtInf_courtL_nn NOT NULL,
CONSTRAINT sys_courtInf_pk PRIMARY KEY (course_Name, star_rating )
);
CREATE TABLE Goft_ForeEver_favorite_courses(
course_Name VARCHAR2(20),
customer_Id VARCHAR2(10),
CONSTRAINT sys_favCourt_PK PRIMARY KEY(course_Name,customer_Id),
CONSTRAINT sys_favCourt_FK1 FOREIGN KEY (customer_Id) REFERENCES Goft_ForeEver_cus(customer_Id),
CONSTRAINT sys_favCourt_FK2 FOREIGN KEY (course_Name) REFERENCES Goft_ForeEver_Course_Info(course_Name)
);
);
Error
Error report - ORA-02256: number of referencing columns must match referenced columns 02256. 00000 - "number of referencing columns must match referenced columns" *Cause: The number of columns in the foreign-key referencing list is not equal to the number of columns in the referenced list. *Action: Make sure that the referencing columns match the referenced columns.
It is because Goft_ForeEver_Course_Info has primary key as
CONSTRAINT sys_courtInf_pk PRIMARY KEY (course_Name, star_rating )
while Goft_ForeEver_favorite_courses that references it has foreign key as
CONSTRAINT sys_favCourt_FK2 FOREIGN KEY (course_Name) REFERENCES Goft_ForeEver_Course_Info(course_Name)
See? You're referencing COURSE_NAME, STAR_RATING composite key by COURSE_NAME only - that won't work.
Therefore, either remove STAR_RATING from the primary key in Goft_ForeEver_Course_Info, add STAR_RATING to Goft_ForeEver_favorite_courses, or redesign everything alltogether.
Illustration (SQL*Plus, which points to the error):
SQL> CREATE TABLE Goft_ForeEver_favorite_courses(
2 course_Name VARCHAR2(20),
3 customer_Id VARCHAR2(10),
4 CONSTRAINT sys_favCourt_PK PRIMARY KEY(course_Name,customer_Id),
5 CONSTRAINT sys_favCourt_FK1 FOREIGN KEY (customer_Id) REFERENCES Goft_ForeEver_cus(customer_Id),
6 CONSTRAINT sys_favCourt_FK2 FOREIGN KEY (course_Name) REFERENCES Goft_ForeEver_Course_Info(course_Name)
7 );
CONSTRAINT sys_favCourt_FK2 FOREIGN KEY (course_Name) REFERENCES Goft_ForeEver_Course_Info(course_Name)
*
ERROR at line 6:
ORA-02270: no matching unique or primary key for this column-list
SQL>
The problem here is you have declared the "course_Name" along with "star_rating" column as composite primary key in Goft_ForeEver_Course_Info table whereas you are referencing only one column "course_Name" in sys_favCourt_FK2 foreign key declaration in Goft_ForeEver_favorite_courses table.
CREATE TABLE Route(
RouteNo VARCHAR(10),
Origin VARCHAR(30),
Destination VARCHAR(30),
DepartureTime VARCHAR(15),
SerialNo VARCHAR(5),
ArrivalTime VARCHAR(15),
PRIMARY KEY(RouteNo) );
CREATE TABLE Employee(
EmployeeID VARCHAR(5) NOT NULL,
Name VARCHAR(30),
Phone NUMBER,
JobTitle VARCHAR(30),
PRIMARY KEY(EmployeeID) );
CREATE TABLE Flight(
SerialNo VARCHAR(5),
RouteNo VARCHAR(5),
FlightDate DATE,
ActualTD VARCHAR(10),
ActualTA VARCHAR(10),
PRIMARY KEY(SerialNo, RouteNo, FlightDate),
FOREIGN KEY(RouteNo) REFERENCES Route(RouteNo),
FOREIGN KEY(SerialNo) REFERENCES Airplane(SerialNo) ); -- does Airplane table exists ?
CREATE TABLE CrewAssigment(
EmployeeID VARCHAR(5),
RouteNo VARCHAR(5),
FlightDate DATE,
Role VARCHAR(45),
Hours INT,
PRIMARY KEY(EmployeeID, RouteNo, FlightDate),
FOREIGN KEY(EmployeeID) REFERENCES Employee(EmployeeID),
FOREIGN KEY(RouteNo) REFERENCES Route(RouteNo),
FOREIGN KEY(FlightDate) REFERENCES Flight(FlightDate) );
Select * from CrewAssignment
This is my code where I'm getting an error in the CrewAssignment table and above are the tables where the foreign key is referenced from.
Error report -
ORA-02270: no matching unique or primary key for this column-list
02270. 00000 - "no matching unique or primary key for this column-list"
*Cause: A REFERENCES clause in a CREATE/ALTER TABLE statement
gives a column-list for which there is no matching unique or primary
key constraint in the referenced table.
*Action: Find the correct column names using the ALL_CONS_COLUMNS
catalog view
A few objections.
This is clearly an Oracle question, not MySQL. How do I know? ORA-02270 is an Oracle database error code; pay attention to tags you use.
You should use VARCHAR2 datatype instead of VARCHAR. Why? Oracle recommends so.
create table flight fails first as it references the airplane table, and it doesn't exist yet (at least, not in code you posted)
error you're complaining about is due to create table crewassignment. One of its foreign keys references the flight table:
FOREIGN KEY(flightdate) REFERENCES flight(flightdate)
but flight's primary key is composite, made up of 3 columns:
PRIMARY KEY(serialno,
routeno,
flightdate)
which means that you can't create that foreign key.
So, what to do? No idea, I don't know rules responsible for such a data model. Either modify primary key of the flight table, or modify foreign key constraint of the crewassingment table.
Perhaps you could add a new column to flight table (made up of a sequence (or identity column, if your database version supports it) and then let the crewassignment table reference that primary key. Columns you currently use as a primary key (serialno, routeno, flightdate) would then switch to unique key.
I use oracle and I try to have a recursive relation
CREATE TABLE "EVENT"
(
"EVENT_ID" NUMBER(18) NOT NULL, //primary key
"NAME" VARCHAR(20) NULL,
"RELATED_EVENT_ID" NUMBER(18) NULL //foreign key
);
Event 1 parent is Event 2....
When I try to create this table, I get this error.
ALTER TABLE "EVENT"
ADD CONSTRAINT "FK_RELATED_EVENT_ID"
FOREIGN KEY ("RELATED_EVENT_ID") REFERENCES "EVENT" ("RELATED_EVENT_ID")
Error report -
SQL Error: ORA-02270: no matching unique or primary key for this column-list
02270. 00000 - "no matching unique or primary key for this column-list"
*Cause: A REFERENCES clause in a CREATE/ALTER TABLE statement
gives a column-list for which there is no matching unique or primary
key constraint in the referenced table.
*Action: Find the correct column names using the ALL_CONS_COLUMNS
catalog view
You have two problems:
There is no primary key constraint on this table.
The foreign key constraint you defined has RELATED_EVENT_ID referencing RELATED_EVENT_ID. I suspect that was just a typo.
Change your table definition to:
CREATE TABLE EVENT
(EVENT_ID NUMBER
NOT NULL
CONSTRAINT PK_EVENT
PRIMARY KEY
USING INDEX,
NAME VARCHAR2(20),
RELATED_EVENT_ID NUMBER);
Then add the foreign key constraint as
ALTER TABLE EVENT
ADD CONSTRAINT EVENT_FK1
FOREIGN KEY (RELATED_EVENT_ID) REFERENCES EVENT(EVENT_ID);
db<>fiddle here
EDIT
Note that the better way to handle this is to use a junction table, such as:
CREATE TABLE EVENT_EVENT
(EVENT_ID1 NUMBER
CONSTRAINT EVENT_EVENT_FK1
REFERENCES EVENT(EVENT_ID),
EVENT_ID2 NUMBER
CONSTRAINT EVENT_EVENT_FK2
REFERENCES EVENT(EVENT_ID),
CONSTRAINT PK_EVENT_EVENT
PRIMARY KEY (EVENT_ID1, EVENT_ID2)
USING INDEX);
Then you can drop the RELATED_EVENT_ID column from EVENT as you no longer need it.
According to oracle document :
Foreign key specifies that the values in the column must correspond to values in a
referenced primary key or unique key column or that they are NULL.
In your case, create primary key on column (EVENT_ID) and use it in reference clause as following:
ALTER TABLE "EVENT"
ADD CONSTRAINT "FK_RELATED_EVENT_ID"
FOREIGN KEY ("RELATED_EVENT_ID")
REFERENCES "EVENT" ("EVENT_ID") -- this
Now, use EVENT2's EVENT_ID as RELATED_EVENT_ID in EVENT1 record to make EVENT2 as parent of EVENT1.
Cheers!!
I have a table with three columns, [Id,QTY,Date]. out of these three, two columns [id and date], should be set as primary keys, because I need to fetch the record one by one, from this table, into a reference.
the data to be inserted into this table is
101,10,NULL
101,20,201220
101,7,201440
102,5,null
102,8,201352
date is in yyyyww format
How do I define two columns as composite primary keys when they have null values, duplicates?
alter table abc add constraint pk primary key (ID, DATE);
if I try to alter the table the error appears
Error report:
SQL Error: ORA-01449: column contains NULL values; cannot alter to NOT NULL
01449. 00000 - "column contains NULL values; cannot alter to NOT NULL"
*Cause:
*Action:
Using table level constraint, you can use this query
alter table your_table add constraint pkc_Name primary key (column1, column2)
but first you need to declare the columns NOT NULL. All parts of a primary key need to be NOT NULL.
The column name of your table is ID and it is still null and non-unique, how is it possible. If it is primary key of other table try adding a surrogate key column for this table and make it primary key.
In case of composite primary key, it should have atleast one not null value(For each row) in the combination of columns. And the combination of column must be unique at all case.
For further details check, http://docs.oracle.com/cd/B10500_01/server.920/a96524/c22integ.htm
Correction - If composite primary key is made up of 3 columns, then no column (among 3) can hold NULL value. And the combination of those 3 columns must be unique.
E.g. (1,2,2)
(1,2,1)
(2,2,1)
(1,2,2) - not valid