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  • 1. SQL 2009 By Cathie Usher 1 SQL 2 ©Chisholm Institute
  • 2. Introduction to SQL SQL stands for Structured Query Language In simple terms it is a universal language that permits the construction of tables and the manipulation of Data that lies within a table. SQL is extensively used in many areas of i d bl i i l di f industry and is fast di f becoming the backbone of Internet display and functionality. In this section we concentrate on the construction and population of tables. This area is referred as the Data Definition Language of SQL (DDL). The following 2 sections concentrate on Data Manipulation Language (DML) where we do the actual queries. You will also be required to create tables yourself and perform some fundamental exercises in the Tutorials Tutorials. 3 Introduction to SQL  SQL consists of two sub languages:  DML (Data manipulation language)  DDL (Data definition language)  SQL is relatively easy to learn.  SQL is a non-procedural (declarative) language. Users need only specify what data they want, not how this data is found.  ANSI prescribes a standard SQL.  Commercial Relational DBMS implement a standard SQL core core.  IBM initiated SQL in 1973. In 1983 the International Standards Organization (ISO) began to develop a standard for relational database languages based on SQL. The latest standard is SQL2 or SQL-92, but SQL3 is now under consideration and will include OO features. 4 ©Chisholm Institute
  • 3. Structured Query Language (SQL)  Data Definition Language (DDL) D t D finiti n L n involves  Data types (Characters, Dates etc)  Creating tables and basic data management (Create, identifying Primary and Foreign Keys etc)  Advanced Data Management the variation and changes to tables that exist 5 Vocabulary The following terminologies are used in this area of SQL CREATE TABLE COMMIT INSERT DROP TABLE DATA TYPE 6 ©Chisholm Institute
  • 4. DML, DDL and Transaction Control  Data Manipulation Language  Query or manipulate the data in database tables  Commands: SELECT, INSERT, UPDATE, DELETE  Data Definition Language  Change the database structure  Commands: CREATE, ALTER, DROP, GRANT, REVOKE  Transaction Control  Organise commands into logical transactions and commit them to the database or roll them back.  Commands: COMMIT, ROLLBACK, SAVEPOINT 7 Common Data Types  Before we can create tables Data Type Format Standard we need to know about Numeric NUMBER(L,D) NUMBER(L D) Oracle data types. INTEGER ANSI Here is a SMALLINT ANSI summary of the data types DECIMAL(L,D) ANSI and their formats for Character CHAR(L) Oracle both Oracle and ANSI if d VARCHAR2(L) Oracle different. Date DATE Oracle 8 ©Chisholm Institute
  • 5. Values allowed by data types Here is a list of the values that are allowed and the method of predefining them.  SMALLINT whole no -32,766 t 32 767 h l n 32 766 to 32,767  INTEGER whole no -2,147,483,647 to 2,147,483,647  DECIMAL(L,D) max of L digits, of which D digits follow the decimal point  CHAR(L) L characters from 0 to 255, fixed storage length  VARCHAR2(L) L characters from 0 to 255, variable storage length 9 Data Definition Commands It is critical when creating the tables that we define the Primary and Foreign Keys as displayed on the Database Schema and the consequential Network diagram.  These commands relate in particular to the creation of tables.  DDL implement Integrity Constraints Entity Integrity  PRIMARY KEY is NOT NULL Referential Integrity  FOREIGN KEY 10 ©Chisholm Institute
  • 6. Creating aTable (1)  The CREATE TABLE statement sets up a table in which rows of data can be stored. h h fd d  In its simplest form this is:  CREATE TABLE name (column_name data_type l d column_constraint); 11 Creating a Table (1) sql> CREATE TABLE DEPARTMENT (DEPT_CODE CHAR(1) NOT NULL, DNAME VARCHAR(25) NOT NULL, MAIL_NO CHAR(2) NOT NULL, PRIMARY KEY (DEPT_CODE)); 12 ©Chisholm Institute
  • 7. Creating the Table (2) sql> CREATE TABLE EMPLOYEE (EMP_ID CHAR(3) NOT NULL, ENAME VARCHAR(25) NOT NULL NULL, DEPT CHAR(1) NOT NULL, MANAGER CHAR(3), DATE_JOINED DATE, DOB DATE, PRIMARY KEY (EMP ID) (EMP_ID), FOREIGN KEY (MANAGER) REFERENCES EMPLOYEE, FOREIGN KEY (DEPT) REFERENCE DEPARTMENT); Note: This table cannot be created until the Department table has been created, as it references the Department table. 13 SQL A simple sql statement that retrieves data from a table has the following key structure. Keywords are in capitals SELECT data you want to retrieve - usually column names FROM table-name WHERE meeting this criteria – usually column-name matches a value(s) SELECT empno, name, salary FROM employee WHERE salary > 50000  SELECT empno, name, salary FROM employee WHERE salary > 50000 14 ©Chisholm Institute
  • 8. Result Set The result of a Select Statement is often referred to as the Result Set. (That's we will call it anyway). An SQL statement is said to 'return' some data via Q m m the result set. The result set is often displayed on the screen but it could be sent to a printer, saved to a file, passed to a program or application etc.  People often mean 'the result set' when they say  "The SQL statement returns / displays / lists / outputs some data" 15 SELECT item list FROM table-name  SELECT < item-list [ [AS] <alias>] >…  The item list is usually a list of column-names or formula  The sequence of columns in the result set is determined by th b the order of expressions i th it d f i in the item-list li t SQL statement Output Col Sequence SELECT empno, name, salary FROM employee In item-list sequence SELECT empno, salary, name FROM employee In item-list sequence SELECT * FROM employee As listed in table def SELECT name, salary, salary * 1.1 FROM employee In item-list sequence item list SELECT name, (salary * 1.1) FROM employee " SELECT name, (salary * 1.1) "New_Salary" FROM " emplo SELECT name AS "Employee Name", salary FROM " emplo 16 ©Chisholm Institute
  • 9. Select Distinct  SELECT [ALL / DISTINCT] <item-list >… firstname surname dept Ted Smith 1  ALL is the default. All possible records are return in the result set. Ted Jones 2  DISTINCT eliminates duplicate  records in the result set. John Jones 1 Ted Jones 1 SELECT DISTINCT dept SELECT DISTINCT FROM employee firstname, dept FROM … firstname dept dept 1 Ted 1 2 Ted 2 John 1 17 Order By The Order By clause specifies the sequence of records in the result- set. • The order is specified by the column number or the column name of the result-set. • Multiple columns can be specified. • Each column may be ordered in ASCending or DESCending sequence (descending is the default) If no order by clause is specified, the result set may be ordered by specified the physical sequence of records in the table. However, this would produce different results if the physical order is ever changed. 18 ©Chisholm Institute
  • 10. Order By  SELECT … FROM … [ ORDER BY <column-name / column-no> [ASC / DESC] [,…] ] SELECT empno, name, salary FROM EMPLOYEE ORDER BY name  result set records are in ascending name sequence s lt s t ds i s di m s SELECT empno, name, salary FROM EMPLOYEE ORDER BY name ASC  result set records are in ascending name sequence SELECT empno, name, salary FROM EMPLOYEE ORDER BY name DESC  result set records are in descending name sequence SELECT empno, name, salary FROM EMPLOYEE ORDER BY salary DESC, empno ASC  result set records are in descending salary sequence. Within each sequence salary, records are listed in ascending employee number sequence SELECT empno, name, salary FROM EMPLOYEE ORDER BY 3, 1  result set records are in ascending salary sequence. Within each salary, records are listed in ascending employee number sequence 19 WHERE clause  SELECT … FROM …  [ WHERE <search-condition> ]  [ ORDER BY …  The WHERE clause specifies the criteria that a record must meet to be included in the result set.  …WHERE surname = "Smith"…  …WHERE salary > 50000…  …WHERE salary <> 50000…  20 ©Chisholm Institute
  • 11. Data Types  When specifying a value stored in a character field you must use quotes around the value you search for.  e.g. e g Select * from employee where empname = "Smith" Smith  Some DBMSs require the use of " double quotes while others use ' single quotes. Some DBMSs will accept either.  Most DBMSs are case-sensitive. Ie. 'SMITH' is not equal to 'Smith'  There is usually a SQL setting to turn case-sensitivity on/off. 21 Data Types  When specifying a value stored in a numeric field you should not use quotes around the value you search for. Do no use commas between thousands. Decimals are OK.  e.g. select * from employee where salary > 29999.99 22 ©Chisholm Institute
  • 12. Summary  SELECT - FROM - WHERE Syntax  SELECT  * shows all rows distinct d  d distinct shows only unique rows h l  select list specifies what columns to display, usually a set of column names  FROM table specification  can be more than one table name here  [WHERE search condition]  specifies which rows to display  [GROUP BY column name] G P B l  specifies columns used to define groups  [HAVING search condition]  specifies which groups to exclude from display  [ORDER BY ordering specification]  specifies how to order results 23 Activity  Complete Tut 1. 24 ©Chisholm Institute
  • 13. Multiple criteria in the Where Clause Use AND / OR when your query needs to meet multiple criteria.  Some simple examples: SELECT * FROM employee WHERE surname = 'SMITH' OR surname = 'JONES' SELECT * FROM employee WHERE salary > 20000 AND salary < 30000  Confused about whether to use AND or OR or ranges? Consider a single row. Can the surname equal Smith AND Jones. No. Draw a simple graph when dealing with ranges ranges. 0 10000 20000 30000 40000 > 20000 < 30000 AND includes range common to both lines OR includes range covered by either line 25 And Operator  The AND operator is used in the where clause.  It evaluates and merges two conditions  It returns results only when both conditons are TRUE. AND Condition 1 True Condition 1 False Condition 2 True TRUE FALSE Condition 2 False FALSE FALSE  Consider the clause: Age Sex Result  …WHERE AGE >20 AND SEX = ‘M WHERE M… 18 M F FALSE E 19 F FALSE 21 F FALSE 22 M TRUE 26 ©Chisholm Institute
  • 14. OR Operator The OR operator is used in the where clause. It evaluates and merges two conditions It returns results only when either conditions are TRUE. t e ther cond t ons E. OR Condition 1 True Condition 1 False Condition 2 True TRUE TRUE Condition 2 False TRUE FALSE Age Sex Result 18 M TRUE 19 F FALSE Consider the clause: 21 F TRUE …WHERE AGE >20 OR SEX = ‘M… 22 M TRUE 27 Multiple operators Where multiple operators exist, evaluate one operator at a time then the next, then the next… Consider … WHERE AGE >19 AND SEX = 'F' AND HEIGHT = '166' and WEIGHT > 50 Age Sex Height Weight  Evaluate AGE > 19 AND SEX = 'F' 24 F 171 86  Evaluate TRUE AND HEIGHT > 166  Evaluate TRUE AND WEIGHT > 50 Age Sex Height Weight  Evaluate AGE > 19 AND SEX = 'F' 24 M 183 93 28 ©Chisholm Institute
  • 15. ANDs and ORs  When both AND and OR operators are used in the where clause,  the AND operators take precedence and are evaluated first.  Consider …  WHERE AGE <17 OR AGE > 23 AND SEX = 'F' 17 Age Sex Height 24 M 180  Evaluate AGE > 23 AND SEX = 'F' first  WHERE SEX = 'M' OR AGE > 22 AND SEX = 'F' OR AGE <17 Age Sex Height 21 M 180 29 Parentheses  Operators within parentheses are always evaluated first.  Parentheses can also be used just for readability. Consider … WHERE AGE < 13 OR AGE > 19 AND SEX = 'M' M  Evaluate AGE > 19 AND SEX = 'M' first, then  Evaluate AGE < 13 OR …  WHERE ( AGE < 13 OR AGE > 19 ) AND SEX = 'M'  Evaluate ( AGE < 13 OR AGE > 19 ) first, then  Evaluate … AND SEX = 'M' WHERE (SEX = 'M' OR SEX = 'F') AND ( AGE >18 AND AGE <= 20 )  Eval either (SEX = 'M' OR SEX = 'F') or ( AGE >18 AND AGE <= 20 ) first  The age checking doesn't need parentheses , but it makes reading easier. 30 ©Chisholm Institute
  • 16. NOT The NOT operator negates the experssion to its right. If the <expression> is TRUE, then NOT <expression> is FALSE If the <expression> is FALSE, then NOT <expression> is TRUE Consider … AGE RESULT WHERE AGE >= 20 AND AGE <= 29 24 TRUE 17 FALSE  WHERE NOT ( AGE >= 20 AND AGE <= 29 ) AGE RESULT 24 FALSE 17 TRUE AGE RESULT 24  WHERE NOT AGE >= 20 AND AGE <= 29 17 31 Special Operators  WHERE <column-name> BETWEEN <value/exp> AND <value/exp>  WHERE age BETWEEN 30 and 40  WHERE < column-name > LIKE <string with % wildcards>  WHERE name LIKE 'SMI%'  WHERE name LIKE '%SMITH%'  WHERE < column-name > IN <expression1 [,…]>  WHERE name IN ('JONES', 'BROWN', 'LEE', 'SOO')  WHERE age IN (24, 26, 28, 30)  same as WHERE age = 24 OR age = 26 OR age = 28 OR age = 30 g g g g  WHERE < column-name > IS NULL / IS NOT NULL  WHERE height IS NULL  WHERE name IS NOT NULL 32 ©Chisholm Institute
  • 17. Constraints  Key Constraint or Primary Key Constraint  The key may have any value but cannot be identical to an existing key  The key (or part key if the key is a composite key) cannot be null  Referential Integrity Constraint or Foreign Key Constraint  A foreign key must match a primary key value in another relation or the  foreign key must be null 33  Obtain tutorial 2 from your tutor. 34 ©Chisholm Institute
  • 18. tablename.columnname and aliases  Each column–name used in any SQL statement may be prefixed by the table name.  SELECT empno, name, salary FROM employee  WHERE sex = 'F' AND age => 50  SELECT employee.empno,, employee.salary FROM employee  WHERE = 'F' AND employee.age => 50  A table may be given an alias which can be used throughout the rest of th SQL statement. The alias name is given immediately after f the t t t Th li i i i di t l ft the table name.  SELECT e.empno,, e.salary FROM employee e  WHERE LIKE 'DAV%' AND e.salary => 50000 35 FROM with multiple tables  SELECT … FROM <table1> [table1-alias], <table2> [table2-alias] [,…]  SQL SELECT statements can work with data from more than one table. t bl  The FROM clause specifies which tables will be used.  As column-names may be identical in two different tables, column-names are usually prefixed by the table name SELECT e.empno,, e.salary b.branchaddr FROM employee e, branch b 36 ©Chisholm Institute
  • 19. SQL JOIN  SELECT … FROM <table1> [table1-alias], <table2> [table2-alias] [,…]  [ WHERE … <foreign column-name> = <primary-key column-name> ]  or <primary-key column-name> = <foreign column-name>  Within the Where clause, you specify foreign key column must = the primary key column  SELECT e.empno,, e.salary, b.branchaddr  FROM employee e, branch b  WHERE e branch=b branch e.branch=b.branch  This statement will display all employees and corresponding branch addresses 37 Effects of a missing Join  If the join is missing, then the DBMS will merge data from each row in table 1 with every row in table two. Large tables create very large result sets EMPLOYEE BRANCH Branch BranchAddr EmpNo Name Branch Salary Box Hill 1 Station St 207 John Hawthorn 48000 Smith Hawthorn 1 John St 119 Jane Pitt Box Hill 37500 345 Carol Kent Hawthorn 55000 RESULT SET EmpNo Name Branch Salary BranchCode BranchAddr 207 John Smith Hawthorn 48000 Box Hill 1 Station St 207 John Smith Hawthorn 48000 Hawthorn 1 John St 119 Jane Pitt Box Hill 37500 Box Hill 1 Station St 119 Jane Pitt Box Hill 37500 Hawthorn 1 John St 345 Carol Kent Hawthorn 55000 Box Hill 1 Station St 345 Carol Kent Hawthorn 55000 Hawthorn 1 John St 38 ©Chisholm Institute
  • 20. Multiple Foreign Keys  A relation/ table can EMPLOYEE have multiple foreign keys EmpNo Name Branch Salary Dept 207 John J h Smith Kew K 48000 1 119 Jane Pitt Box Hill 37500 2 345 Carol Kent Hawthorn 55000 2 BRANCH DEPARTMENT Branch BranchAddr BranchPh DeptCode DeptDescr Box Hill 1 Station St 9999-5678 1 Sales Hawthorn 1 John St 9999-2222 2 Admin Kew 1 High St 9999-1234 3 Reception 39 SQL JOIN (a table with 2 foreign keys)  SELECT d.deptdescr, e.branch, e.empno,, b.branchph, e.salary,  FROM employee e, branch b, department d  WHERE e.branch = b.branch  AND e.dept = d.deptcode Jo s employee branch Joins e p oyee to b a c  AND e.salary > 380000 Joins employee to department RESULT SET deptdescr branch EmpNo Name BranchPh Salary Sales Kew 207 John Smith 9999-1234 48000 Admin dm n Hawthorn 3 5 345 Carol Kent arol 9999 9999-2222 55 55000 40 ©Chisholm Institute
  • 21. Multiple Foreign Keys (2) EMPLOYEE  Each table relation can EmpNo Name Branch Salary have foreign key links to 207 John Smith Kew 48000 other tables. 119 Jane Pitt Box Hill 37500 667 John Dill Penrith 75000 BRANCH Branch BranchAddr Region REGION Kew 1 High St ME RegionCode RegionDescr Hawthorn 1 John St ME ME Melbourne East Penrith 1 Puckle St SW SW Sydney West 41 SQL JOIN (3 tables each with a FK )  SELECT, reg.regiondescr  FROM employee e, branch b, region reg  WHERE e.branch = b.branch  AND b region = reg.regioncode Joins e p oyee to b a c b.region reg regioncode Jo s employee branch  AND e.empno > 200 Joins branch to region RESULT SET Name RegionDescr John Smith Melbourne East John Dill Sydney West  Notice how this query does not display any columns from the branch table 42 ©Chisholm Institute
  • 22. Drop Table  DROP TABLE <tablename>  You cannot create a table that already exists.  You will need to DROP a table first, if you want to re-create it.  DROP TABLE student;  CREATE TABLE student… 43 DELETE records DELETE <table-name>  WHERE …  DELETE student will delete all rows from the student table  DELETE student WHERE stu_height < 150  will delete all rows fro the student table that meet the criteria.  44 ©Chisholm Institute
  • 23. COUNT  COUNT counts the number of records in a table (that meet a criteria).  PART ( partnumb, partdesc, unonhand, itemclss, wrhsnumb, unitprce )  SELECT COUNT(*) FROM part  SELECT COUNT(partnumb) FROM part  SELECT COUNT(*) FROM part WHERE itemclass = 'HW'  SELECT COUNT(partnumb) FROM part WHERE itemclass = 'HW' 45 SUM , AVERAGE , MAX , MIN  SUM totals a column (that meet a criteria).  ORDLNE (ordnumb, partnumb, numbord, quotprce )  SELECT SUM( numbord ) FROM ordlne  SELECT AVG( numbord ) FROM ordlne  SELECT MIN( numbord ) FROM ordlne  SELECT MAX( numbord ) FROM ordlne  SELECT SUM( numbord * quotprce ) FROM ordlne  SELECT SUM( numbord * quotprce ) FROM ordlne  WHERE partnumb = 'BT04' 46 ©Chisholm Institute
  • 24. GROUP BY  The following statement requires a part number in the criteria.  SELECT SUM( numbord * quotprce ) FROM ordlne  WHERE partnumb = 'BT04'  Imagine if you had 1000 products. You would have to type 1000 product codes.  The GROUP BY clause, will display an aggregate total for each 'group'  The following records are 'grouped' by order number.  SELECT ordnumb, SUM( numbord * quotprce ) ordnumb Sum  FROM ordlne 12489 164.45  GROUP BY ordnumb 12491 714.94 12494 700.00 12495 115.90 12498 65.70 12500 402.99 12504 217.98 47 GROUP BY rules  An aggregate expression contain aggregate words such as count, sum…  The select statement may contain any mixture of aggregate and non-aggregate expressions.  Every non aggregate expression in the select clause must appear in the Group By Clause p y  Aggregate expressions in the Select clause do not appear in the Group By clause  A subtotal will be calculated for each change in the non-aggregate column values  SELECT wrhsnumb,  itemclss, count(*) wrhsnumb itemclss Part Table  FROM part 3 HW 2 SG Result Set  GROUP BY 1 SG  wrhsnumb, wrhsnumb itemclss 3 HW wrhsnumb itemclss count 2 AP 1 SG 2 3 AP 2 AP 1 3 HW 1 SG 2 SG 2 3 HW 3 AP 1 2 SG 3 HW 4 48 ©Chisholm Institute
  • 25. HAVING  Having 'works on' the results of the Group By. wrhsnumb itemclss count  The previous Group By showed: 1 SG 2 2 AP 1  Suppose we only wanted to deta ls of product details 2 SG 2  classes that had more than one item. 3 AP 1 3 HW 4  That means we want to specify a criteria based on the result of the Group By.  The HAVING clause is used to do this. Do not use the WHERE clause.  The HAVING clause must use a aggregate expression from the SELECT clause.  SELECT wrhsnumb, itemclss, count(*)  FROM part t  GROUP BY wrhsnumb, itemclss  HAVING count(*) >= 2 49 Review  SELECT Column names / expressions / aggregate expressions  Column names should be preceded by table names  especially when multiple tables are used  FROM Table names (aliases may be used for Table Names)  WHERE Specifies criteria that rows must match to be selected selected.  This is where 'joins' are specified in Oracle 8.  The join is usually foreign-key column = primary key column.  GROUP BY Calculate subtotals. All non-aggregate SELECT expressions  must be included here  HAVING Used in conjuction with Group By. Specifies criteria that  Group By aggregate expressions must match to be selected.  The criteria is based on the results of the Group By.  Only aggregate expressions from the SELECT clause may  appear here.  ORDER BY Specifies the sequence of rows in the RESULT SET 50 ©Chisholm Institute
  • 26. Sub Queries  Some queries cannot be completed in a simple single SQL statement.  Determine the average unit price of all parts.  OK SELECT AVG(unitprce) from part  ERROR SELECT * from price WHERE unitprce > AVG( unitprce )  Aggregate commands are not allowed in the WHERE clause.  However subqueries are allowed.  A subquery is a complete SQL statement WITHIN another SQL statement. 51 Sub Query Examples  SELECT *  FROM part  WHERE unitprce > ( SELECT AVG(unitprce) FROM part )  SELECT partnumb , partdesc  FROM part  WHERE partnumb NOT IN ( SELECT DISTINCT partnumb FROM ordlne ) 52 ©Chisholm Institute
  • 27. Dates & related functions  Using today's date:  SELECT sysdate FROM dual 25-MAY-02  SELECT *  FROM orders, dual orders  WHERE orddte < sysdate ---- No Join necessary  Convert Character String to Date  to_date('25-dec-02')  SELECT TO_DATE('25-dec-02') - sysdate FROM dual ----- 151.65480  SELECT ROUND (TO_DATE('25-dec-02') – sysdate) FROM dual ------ 152 53 References  A List of Oracle Functions  This site gives a list of the functions that are use the most in Oracle.  SQL*Plus User's Guide and Reference, Release 8.1.5  Guide that explains all the concepts behind PL/SQL and illustrates every facet of the language.  Oracle8i SQL Reference Reference that contains a complete description of the (SQL)  Oracle Underground FAQ  A site giving a wide variety of topics on Oracle.  Oracle FAQ F O l FAQs Forum  Post your questions on anything about Oracle Developer. You can also learn a lot from others' experience and answers. 54 ©Chisholm Institute
  • 28. Self Joins  Suppose we have an Employee Table.  The Manager column contains the employee number of each employee's manager.  The Manager column may contain nulls EMPLOYEE  as some managers will not have a EmpNo Name Salary Manager  manager of their own. 119 Jane Pitt 37500 543  To extract employee & manager details,  we must employee as 2 different tables.207 John 48000 543 Smith  SELECT Employee_Name, 345 Carol Kent 55000 543  Manager_Name 543 Dave Bligh 70000 ┴  FROM employee AS emp,  employee AS mgr l Column Heading  WHERE emp.manager = mgr.empno Same table – 2 aliases 55 Inner Joins  The join syntax we have used so far in often referred to as a INNER JOIN.  The result set only includes rows that have matching data from both tables.  "Show me a list of all parts and show me quantities sold"  SELECT o.ordnumb, o.numbord, p.partnumb, p.partdesc  FROM ordlne o, part p o  WHERE o.partnumb = p.partnumb ordnumb partnumb numbord partdesc 12489 AX12 11 IRON 12491 BT04 1 STOVE 12491 BZ66 1 WASHER 12494 CB03 4 BIKE 12495 CX11 2 MIXER 12498 AZ52 2 SKATES 12498 BA74 4 BASEBALL 12500 BT04 1 STOVE 12504 CZ81 2 WEIGHTS  Parts BH22 & CA14 are not in the list – as they have not been ordered 56 ©Chisholm Institute