OK so here is the table and data types I am attempting to create in sql developer:
Table_Name interview
Field_Name e_number, pos_id, date, time, awarded
Data_Type varchar2(9), varchar2(15), date, number(9), varchar2(3)
Nulls_Allowed
Primary_Key y, y, n, n, n
Unique y, y, n, n, n
Foreign_Key
Comments
Here is the sql I am trying to use:
CREATE TABLE interview(
e_number VARCHAR2(9) NOT NULL UNIQUE,
pos_id VARCHAR2(15) NOT NULL UNIQUE,
date DATE NOT NULL,
time NUMBER(8) NOT NULL,
awarded VARCHAR2(3),
CONSTRAINT pk_interview PRIMARY KEY (e_number, pos_id),
CONSTRAINT fk_e_number FOREIGN KEY (e_number) REFERENCES student
(e_number),
CONSTRAINT fk_pos_id FOREIGN KEY (pos_id) REFERENCES position
(pos_id)
Can someone to tell me where I have "invalid identifier"? Cause I am completely lost.
CREATE TABLE interview(
e_number VARCHAR2(9) NOT NULL UNIQUE,
pos_id VARCHAR2(15) NOT NULL UNIQUE,
"date" DATE NOT NULL,
"time" NUMBER(8) NOT NULL,
awarded VARCHAR2(3),
CONSTRAINT pk_interview PRIMARY KEY (e_number, pos_id),
CONSTRAINT fk_e_number FOREIGN KEY (e_number) REFERENCES student (e_number),
CONSTRAINT fk_pos_id FOREIGN KEY (pos_id) REFERENCES position (pos_id)
);
As suggested by #Remy_Lebeau, #CLifford, and #amdixon
date and time are reserved words (see this post), so enclose them in quotations. Also, add right parentheses and semicolon to close your table declaration.
Related
So this is my code for a homework
CREATE TABLE workorders
(
wo# NUMBER(5) PRIMARY KEY,
proj# VARCHAR(10) NOT NULL FOREIGN KEY REFERENCES project(proj#),
wo_desc VARCHAR(30) NOT NULL UNIQUE,
wo_assigned VARCHAR(30),
wo_hours NUMBER(5) NOT NULL CHECK(wo_hours>0),
wo_start DATE,
wo_due DATE,
wo_complete CHAR(1),
CONSTRAINT workorders_wo_complete_chk CHECK(wo_complete in('Y','N'))
);
I could not figure out why oracle apex won't let me create this table, it says
ORA-00907: missing right parenthesis
But I double-checked so many times and I think I do have all the parenthesis? What did I do wrong here?
Thanks in advance
I just want to create this table under these constreaints but I could find any errors that I know of.
Oracle's error messages are often not particularly helpful, and the best thing to do is to go through your code, line by line, commenting out each line until you isolate the problem.
In this case the offending line is
proj# VARCHAR(10) NOT NULL FOREIGN KEY REFERENCES project(proj#),
and the problem is that you don't use the words FOREIGN KEY to define a foreign key - you just need to specify what it references. So this should be
proj# VARCHAR(10) NOT NULL REFERENCES project(proj#),
and then you'll be fine.
db<>fiddle here
When defining an inline constraint, the FOREIGN KEY terms are not used:
proj# VARCHAR2(10) NOT NULL
REFERENCES project(proj#)
Note: Oracle uses VARCHAR2 and VARCHAR is an alias to VARCHAR2 and it is considered best-practice to use VARCHAR2 throughout.
However, those keywords are required when you define an out-of-line foreign key (but then you would be missing a comma and the column identifier):
proj# NOT NULL,
FOREIGN KEY (proj#) REFERENCES project (proj#)
Note: If you are using a foreign key constraint then you do not need to define the data type and Oracle will implicitly use the data type of the column being referenced.
The complete code using (named) inline constraints throughout would be:
CREATE TABLE workorders
(
wo# NUMBER(5)
CONSTRAINT workorders__wo#__pk PRIMARY KEY,
proj# -- Note: do not need the data type as the FK will define it.
NOT NULL
CONSTRAINT workorders__proj#__fk REFERENCES project(proj#),
wo_desc VARCHAR2(30)
NOT NULL
CONSTRAINT workorders__wo_desc__u UNIQUE,
wo_assigned VARCHAR2(30),
wo_hours NUMBER(5)
NOT NULL
CONSTRAINT workorders__wo_hours__chk CHECK(wo_hours>0),
wo_start DATE,
wo_due DATE,
wo_complete CHAR(1)
CONSTRAINT workorders_wo_complete_chk CHECK(wo_complete in('Y','N'))
);
and using (named) out-of-line constraints throughout:
CREATE TABLE workorders
(
wo# NUMBER(5),
proj# -- Note: do not need the data type as the FK will define it.
NOT NULL,
wo_desc VARCHAR2(30)
NOT NULL,
wo_assigned VARCHAR2(30),
wo_hours NUMBER(5)
NOT NULL,
wo_start DATE,
wo_due DATE,
wo_complete CHAR(1),
CONSTRAINT workorders__wo#__pk PRIMARY KEY(wo#),
CONSTRAINT workorders__proj#__fk FOREIGN KEY (proj#) REFERENCES project(proj#),
CONSTRAINT workorders__wo_desc__u UNIQUE(wo_desc),
CONSTRAINT workorders_wo_complete_chk CHECK(wo_complete in('Y','N')),
CONSTRAINT workorders__wo_hours__chk CHECK(wo_hours>0)
);
fiddle
I am creating a table in a command SQL sections into a script already populated I have created several tables already but in this one I get a message saying
ORA-00902: invalid datatype
CREATE TABLE Weapons
(
id NUMBER(4),
name VARCHAR2(30),
damage NUMBER(4),
company_id VARCHAR2 (10),
CONSTRAINT pk_Weapons PRIMARY_KEY(id),
CONSTRAINT fk_Weapons_company
FOREIGN_KEY(company_id) REFERENCES Company(id),
CONSTRAINT fk_Weapons_ammo
FOREIGN_KEY(ammo_id) REFERENCES Ammo(id)
);
In the CONSTRAINT, it should be FOREIGN KEY and not FOREIGN_KEY. Also it should be PRIMARY KEY, not PRIMARY_KEY.
There is no underscore required as per syntax. So the query will be:
CREATE TABLE Weapons (
id NUMBER(4),
name VARCHAR2(30),
damage NUMBER(4),
company_id VARCHAR2(10),
CONSTRAINT pk_Weapons PRIMARY KEY(id),
CONSTRAINT fk_Weapons_company FOREIGN KEY(company_id) REFERENCES Company(id),
CONSTRAINT fk_Weapons_ammo FOREIGN KEY(ammo_id) REFERENCES Ammo(id)
);
About Foreign Keys: https://www.techonthenet.com/oracle/foreign_keys/foreign_keys.php
About Primary Keys: https://www.techonthenet.com/oracle/primary_keys.php
Here's a working example. I've created the AMMO table (whose description you didn't post, so I used only the ID column so that the foreign key constraint wouldn't fail). Pay attention to comments I wrote within the code.
SQL> create table ammo
2 ( id VARCHAR2(10),
3 CONSTRAINT pk_ammo PRIMARY KEY(id) );
Table created.
SQL> CREATE TABLE Company
2 ( id VARCHAR(3),
3 name VARCHAR(30), --> switch from CHAR to VARCHAR2
4 CONSTRAINT pk_Company PRIMARY KEY(id) );
Table created.
SQL> CREATE TABLE Weapons
2 ( id NUMBER(4),
3 name VARCHAR2(30),
4 damage NUMBER(4),
5 company_id VARCHAR2(3), --> should match COMPANY.ID datatype
6 ammo_id VARCHAR2(10), --> should match AMMO.ID datatype
7 CONSTRAINT pk_Weapons PRIMARY KEY(id),
8 CONSTRAINT fk_Weapons_company FOREIGN KEY(company_id) REFERENCES Company(id),
9 CONSTRAINT fk_Weapons_ammo FOREIGN KEY(ammo_id) REFERENCES ammo(id) );
Table created.
SQL>
In referential integrity constraint, you should match datatypes of the foreign and primary key columns. There's no sense in having a VARCHAR2(10) in the detail table which points to a VARCHAR2(3) column in the master table; you won't be able to put anything longer than 3 characters into the detail table's column anyway (foreign key constraint won't let you).
I'm getting an error from oracle that says "number of referencing columns must match referenced columns."
I want my column recorded_on in the table measurement to reference recorded_on in the table called sample
The column Recorded on in the Sample table must be part of a composite key together with Scientist_Num
The error is coming from
FOREIGN KEY (Recorded_On) REFERENCES Sample(Scientist, Recorded_On, Site_ID)
CREATE TABLE Sample (
Scientist_Num varchar2(5) not null,
Recorded_On date not null,
Site_ID varchar2(4) not null,
Comments clob,
Primary key (Scientist_Num, Recorded_On),
FOREIGN KEY (Scientist_Num) REFERENCES Scientist(Scientist_Num),
FOREIGN KEY (Site_ID) REFERENCES Site(Site_ID)
);
CREATE TABLE Measurement (
Site_ID varchar2(4) not null,
Recorded_On date not null,
Name varchar2(10) not null,
Value varchar2(10),
Outlier_Indicator varchar2(10),
Primary key (Site_ID, Recorded_On, Name),
FOREIGN KEY (Site_ID) REFERENCES Sample(Site_ID),
FOREIGN KEY (Recorded_On) REFERENCES Sample(Scientist, Recorded_On, Site_ID)
);
The Scientist_Num and Recorded_On columns must be in a composite key together.
The answer to my problem and an explanation of what went wrong would be greatly appreciated.
You can create virtual column in sample table:
Recorded_virtual varchar2(5) [GENERATED ALWAYS] AS
(Scientist||Recorded_On||Site_ID) [VIRTUAL]
And create reference to this column:
CONSTRAINT fk_column
FOREIGN KEY (Recorded_On)
REFERENCES Sample(Recorded_virtual )
Foreign key references need to match the primary keys in number and type. So I think you intend:
CREATE TABLE Measurement (
Site_ID varchar2(4) not null,
Scientist_Num varchar2(5) not null,
----^ added for foreign key reference
Recorded_On date not null,
Name varchar2(10) not null,
Value varchar2(10),
Outlier_Indicator varchar2(10),
Primary key (Site_ID, Recorded_On, Name),
FOREIGN KEY (Site_ID) REFERENCES Site(Site_ID),
-------------------------------------^ Presumably you intend the site table
FOREIGN KEY (Scientist_Num, Recorded_On) REFERENCES
Sample(Scientist_Num, Recorded_On)
-----------------^ two columns, both need to already be defined
);
I suspect there are other issues with your data model, but this should fix the syntax error. If you want further help, then ask another question.
i'm creating a few tables which look like this
CREATE TABLE sickness
(
sickness_id number(2),
sickness_name varchar2(20),
PRIMARY KEY (sickness_id)
);
CREATE TABLE cover
(
cover_needed char(1) NOT NULL,
employee_id number(3),
responsibilities varchar2(50),
notes varchar2(50),
PRIMARY KEY (cover_needed, employee_id)
);
this works fine then when i try to make a parent table (see below), i get the error.
ORA-02270: no matching unique or primary key for this column-list
i have however narrowed it down to the last line but i can not for the life of me figure it out, thank you
CREATE TABLE absences
(
absences_id number(2) NOT NULL,
manager_id number(3),
employee_id number(3) NOT NULL,
absence_name varchar2(15) NOT NULL,
sickness_id number(2),
date_from date NOT NULL,
date_to date NOT NULL,
length number(2) NOT NULL,
description varchar2(40),
authorised_by_manager char(1) NOT NULL,
cover_needed char(1) NOT NULL,
half_day char(1) NOT NULL,
PRIMARY KEY (absences_id, manager_id, employee_id),
FOREIGN KEY (sickness_id) REFERENCES sickness (sickness_id),
FOREIGN KEY (cover_needed) REFERENCES cover (cover_needed)
);
This is how you define cover:
CREATE TABLE cover (
. . .
**PRIMARY KEY (cover_needed, employee_id)**
);
You have a composite primary key. Foreign key references need to reference both keys . . . and in the same order.
So:
FOREIGN KEY (cover_needed, employee_id)
REFERENCES cover (cover_needed, employee_id)
I think your data structures and queries would be simpler if you used auto-generated numeric primary keys. That would simplify the foreign key relationships and simplify the queries that connect tables.
I'm receiving this error when trying to create a table and I don't know why:
[2016-07-05 14:08:02] [42000][2270] ORA-02270: no matching unique or primary key for this column-list
This question seems different (to me) from a similar question, because in that question the OP is referencing a table with a composite PK, while I am not.
And while this other question has the same error code, it is because the OP is incorrectly references the primary key, which I don't think I did.
May someone more experienced in SQL educate me?
(A couple of things to note: 1) I know the table/column names have small errors/deviations from convention, but this is for homework, and the teacher requires I have the tables and rows declared exactly his way, even if it's non-conventional. 2) Yes, that's silly; but no, I can't change it or I get marked down.)
CREATE TABLE Student_Course
(
Stu_ID NUMBER(5) NOT NULL,
Course_ID VARCHAR2(8) NOT NULL,
Section# NUMBER(3),
CONSTRAINT pk_stu_crse PRIMARY KEY (Stu_ID, Course_ID),
CONSTRAINT fk_course_id FOREIGN KEY (Course_ID) REFERENCES course(Course_ID),
CONSTRAINT fk_stu_id FOREIGN KEY (Stu_ID) REFERENCES student(Stu_ID),
CONSTRAINT fk_section FOREIGN KEY (Section#) REFERENCES course(Section#)
)
There are only two, small, referenced tables, which are:
CREATE TABLE student
(
Stu_ID NUMBER(5) PRIMARY KEY ,
Lname VARCHAR2(20),
Fname VARCHAR2(20),
Mi CHAR(1),
Sex CHAR(1),
Major VARCHAR2(15),
Home_State CHAR(2)
);
CREATE TABLE course
(
Course_ID VARCHAR2(8) PRIMARY KEY ,
Section# NUMBER(3),
C_Name VARCHAR2(30),
C_Description VARCHAR2(30)
);
A foreign key is a reference to a primary key in another table.
The last constraint CONSTRAINT fk_section FOREIGN KEY (Section#) REFERENCES course(Section#) won't work - Section# isn't a primary key in that table
Section# Must be at least UNIQUE in course table.
If you want to use Section# as a reference for a foreign key, it must be a UNIQUE or a PRIMARY KEY
More information about FOREIGN KEY and constraints
Thanks to good answers, I'm posting my code which I corrected based on help here. Hope my corrections help others in the future.
CREATE TABLE student
(
Stu_ID NUMBER(5) PRIMARY KEY ,
Lname VARCHAR2(20),
Fname VARCHAR2(20),
Mi CHAR(1),
Sex CHAR(1),
Major VARCHAR2(15),
Home_State CHAR(2)
);
CREATE TABLE course
(
Course_ID VARCHAR2(8) ,
Section# NUMBER(3) ,
C_Name VARCHAR2(30),
C_Description VARCHAR2(30),
CONSTRAINT pk_course PRIMARY KEY (Course_ID, Section#)
);
CREATE TABLE Student_Course
(
Stu_ID NUMBER(5) ,
Course_ID VARCHAR2(8) ,
Section# NUMBER(3) ,
CONSTRAINT pk_stu_crse PRIMARY KEY (Stu_ID, Course_ID, Section#),
CONSTRAINT fk_stu FOREIGN KEY (Stu_ID) REFERENCES student(Stu_ID),
CONSTRAINT fk_course_id FOREIGN KEY (Course_ID, Section#) REFERENCES course(Course_ID, Section#)
);