SQL Server Join Examples


This section contains the create, insert and T-SQL code to run the examples from Chapter 4, “The Join Operation” in a SQL Server database. It requires the helper functions RANDOM_DATE and RANDOM_INT from the where clause examples.

CREATE TABLE sales (
  sale_id       NUMERIC NOT NULL,
  employee_id   NUMERIC NOT NULL,
  subsidiary_id NUMERIC NOT NULL,
  sale_date     DATE    NOT NULL,
  eur_value     NUMERIC(17,2) NOT NULL,
  product_id    NUMERIC NOT NULL,
  quantity      NUMERIC NOT NULL,
  junk          CHAR(200),
  CONSTRAINT sales_pk     
     PRIMARY KEY NONCLUSTERED (sale_id),
  CONSTRAINT sales_emp_fk 
     FOREIGN KEY          (subsidiary_id, employee_id)
      REFERENCES employees(subsidiary_id, employee_id)
);
GO

SELECT RAND(0);
GO

WITH generator (n)
  AS (
     SELECT 1
      UNION ALL
     SELECT n + 1
       FROM generator
      WHERE N < 1800
     )
INSERT INTO sales (sale_id
                 , subsidiary_id, employee_id
                 , sale_date, eur_value
                 , product_id, quantity
                 , junk)
SELECT row_number() OVER (ORDER BY sale_date), data.*
  FROM (
       SELECT e.subsidiary_id, e.employee_id
            , [dbo].random_date(0, 3650) sale_date
            , [dbo].random_int(1, 100000)/100 eur_value
            , [dbo].random_int(1, 25) product_id
            , [dbo].random_int(1, 5) quantity
            , 'junk' junk
         FROM employees e
            , generator gen
        WHERE employee_id % 7 = 4
          AND gen.n < employee_id / 5
       ) data
        WHERE DATEPART(weekday, sale_date)
           <> DATEPART(weekday, '2012-01-01')
        ORDER BY sale_date
OPTION(MAXRECURSION 2000);
GO


EXEC sp_updatestats;
GO

Notes:

  • The rows are inserted chronologically to reflect a natural table growth.

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

About the Author

Photo of Markus Winand
Markus Winand tunes developers for high SQL performance. He also published the book SQL Performance Explained and offers in-house training as well as remote coaching at http://winand.at/

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