InterBase: How to create view with a multible tables? - sql

Question

I am using SQL statement to create a view, but all the time I have problems with syntax.
The four tables I have are:
CREATE TABLE "BOOK_ORDER"
(
"ID" INTEGER NOT NULL,
"Open_Date" DATE NOT NULL,
"Close_Date" DATE,
"Student_ID" INTEGER NOT NULL,
"Book_ID" INTEGER NOT NULL,
CONSTRAINT "PK_ORDER_ID" PRIMARY KEY ("ID")
);
ALTER TABLE "BOOK_ORDER" ADD CONSTRAINT "FK_ORDER_BOOK" FOREIGN KEY ("Book_ID") REFERENCES BOOK ("ID") ON UPDATE CASCADE ON DELETE CASCADE;
ALTER TABLE "BOOK_ORDER" ADD CONSTRAINT "FK_ORDER_STUDENT" FOREIGN KEY ("Student_ID") REFERENCES STUDENTS ("STUDENT_ID") ON UPDATE CASCADE ON DELETE CASCADE;
CREATE TABLE "STUDENTS"
(
"STUDENT_ID" INTEGER NOT NULL,
"STUDENT_NAME" VARCHAR(50) NOT NULL,
"TICKET" INTEGER NOT NULL,
"GROUP_ID" INTEGER NOT NULL,
CONSTRAINT "PK_StUDENTS" PRIMARY KEY ("STUDENT_ID")
);
ALTER TABLE "STUDENTS" ADD CONSTRAINT "FK_GROUP" FOREIGN KEY ("GROUP_ID") REFERENCES GROUPS ("GROUP_ID") ON UPDATE CASCADE ON DELETE CASCADE;
CREATE TABLE "GROUPS"
(
"GROUP_ID" INTEGER NOT NULL,
"TITLE" VARCHAR(50) NOT NULL,
"CURATOR" VARCHAR(50) NOT NULL,
"CURATOR_TEL" VARCHAR(20) NOT NULL,
"FAC_ID" INTEGER NOT NULL,
CONSTRAINT "PK_GROUP" PRIMARY KEY ("GROUP_ID")
);
CREATE TABLE "BOOK"
(
"ID" INTEGER NOT NULL,
"CODE" INTEGER NOT NULL,
"Name" VARCHAR(50) NOT NULL,
"Year" DATE NOT NULL,
"Publishing_Office" VARCHAR(50) NOT NULL,
"Language" INTEGER NOT NULL,
CONSTRAINT "PK_BOOK_ID" PRIMARY KEY ("ID")
);
I need to show info about order: OpenDate, CloseDate, Student, StudentGroup, Book.

Answer 1

You create a view with the syntax of CREATE VIEW view_name AS SELECT statement where statement is your regular SELECT statement.
Therefore, you would do this:
CREATE VIEW view_name AS
SELECT BOOK_ORDER.id, BOOK_ORDER.OpenDate, BOOK_ORDER.CloseDate, students.student_name, groups.title, book.name
FROM book_order, students, groups, book
WHERE book_order.student_id = students.student_id AND
book_order.book_id = book.id AND
students.group_id = groups.group_id
The where clause is performing a simple join by including values repeated across tables once. I cannot guarantee this will work, but it is a good start.
Also, to get data from the view, select from it like a regular table with the view as the table name.