Queries and SQL in Access Please use speaker notes for additional information!

Textbook.mdb

Query - all fields, all rows

Query with SQL All columns/fields for all rows/records means that in this case all of the columns/fields are listed in the SELECT clause with their table name in front. The table name also appears in the FROM clause Note that SQL code end with a semi-colon.

SQL versions In this version, the book.ISBN has been changed to ISBN - this has been applied to all columns/fields. The table name is only needed if two tables are being used and the column/field appears on both. In this version, the SELECT * means select all columns/fields. You only need to list the columns/fields by name if you want only specific ones to appear in the results.

Query - AND This is an AND query asking for all books with a year published greater than 1998 AND a price > 40. The results are shown below.

SQL for AND query The SELECT statement is specifying certain fields/columns that should be shown. In this case the fields are ISBN, title, yrpub and price. As you can see the table name is shown in front of the column name in the format book.ISBN etc. The FROM clause specifies the table name. The WHERE clause gives the condition. In this case the condition is the yrpub > 1998 or price > 40.

SQL - AND The SELECT only lists the columns/fields by name because there is no chance of duplication with only one table being used. The WHERE is coded by simply using the column name, the comparison operator and the field being compared against is in quotes because it was defined as a text field. 40 is not in quotes because it was defined as a number (currency) field.

OR Query Yrpub must be greater than 1999 OR price must be greater than 40. Either one is sufficient.

SQL - OR Again I have eliminated the table name in the select because there is no chance for duplication and the multiple parenthesis in the WHERE.

AND - OR The table is shown in ascending order by ISBN. The query wants books with price greater than 40 AND with a pubid of either 001 OR 002.

AND - OR Notice the ORDER BY ISBN clause which accomplishes the ascending sort. Logic: cond A AND either (cond B OR cond C) Note the way the OR is expressed.