by Markus Winand.

SQLBase Example Scripts for “The Join Operation”


This section contains the create and insert code to run the examples from Chapter 4, “The Join Operation in an Gupta/Unify SQLBase database.

CREATE TABLE sales (
  sale_id       INTEGER NOT NULL,
  employee_id   INTEGER NOT NULL,
  subsidiary_id INTEGER NOT NULL,
  sale_date     DATE   NOT NULL,
  eur_value     DECIMAL(13,2) NOT NULL,
  product_id    INTEGER NOT NULL,
  quantity      INTEGER NOT NULL,
  junk          CHAR(200),
  PRIMARY KEY (sale_id),
  FOREIGN KEY (subsidiary_id, employee_id)
   REFERENCES employees
);

CREATE UNIQUE INDEX sales_pk ON sales (sale_id);

INSERT INTO sales (sale_id
                 , subsidiary_id, employee_id
                 , sale_date, eur_value
                 , product_id, quantity
                 , junk)
       SELECT gen.n *2000*30 + e.employee_id * 30 + e.subsidiary_id AS sale_id
            , e.subsidiary_id, e.employee_id
            , SYSDATE - @mod(n+@MICROSECOND(@NOW), 10*365) AS  sale_date
            , (@MOD(@MICROSECOND(@NOW)+n, 9000) + 1000)/100 AS eur_value
            , @MOD(@SECOND(@NOW)+n/9000*29,29) AS product_id
            , @MOD(@SECOND(@NOW)+n/9000*26,5) AS quantity
            , 'junk'
         FROM employees e
          , generator_4k gen
        WHERE @MOD(employee_id, 7) = 4
              AND gen.n < 1800
          AND gen.n < employee_id / 5 ;

Notes:

  • The rows are NOT inserted chronologically

  • Only a small fraction of employees have sales at all.

About the Author

Photo of Markus Winand

Markus Winand teaches efficient SQL—inhouse and online. He minimizes the development time using modern SQL and optimizes the runtime with smart indexing. His book entitled SQL Performance Explained has become standard reading.

Buy his Book on Amazon

Cover of “SQL Performance Explained”: Squirrel running on grass

The essence of SQL tuning in 200 pages

Buy on Amazon
(paperback only)

Paperback and PDF also available at Markus’ store.

Hire Markus

…to answer your current SQL questions.

The quick and easy way to benefit from his extensive knowledge and experience.
Learn more »

“Use The Index, Luke!” by Markus Winand is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Unported License.
Legal | Contact | NO WARRANTY | Trademarks | Privacy | CC-BY-NC-ND 3.0 license