Many of the most frequently asked questions on queries can be answered by 
referring to the documentation, searching Help, reviewing the step by step 
examples in the sample database Solutions or downloading Knowledgebase 
articles from CompuServe.

The User's Guide includes many common tips, such as:
  Recommended Books on Database Design - Chapter 2, page 39
  Creating Parameter Queries - Chapter 12, page 274
  Prompting for Criteria from a Form (Query By Form) - Chapter 12, page 278
  Creating Union Queries - Chapter 12, page 288

Some common questions answered in Help are:
  How to work with Nulls - "Working with Nulls and Zero-Length Strings"
  SubQueries - "Creating a Subquery" and "SQL Subqueries"
  Improving Performance - "Optimizing Microsoft Access Performance"
  Rushmore Technology - "Optimizing Queries with Rushmore Technology"

More information on optimizing queries can be found in the following 
Knowledge Base articles:
  Q112112 INF: How to Optimize Microsoft Access Version 2.0 Queries 
  Q112117 INF: How to Optimize Microsoft Access Version 2.0 Performance 
  Q99321 INF: Tips for Optimizing Queries on Attached SQL Tables     
  Q113553 INF: Tech*Ed 94 Sessions on Queries in MS Access 2.0        

Many questions on queries are related to prompting the user for input and
using that input in a query.  The Solutions sample database contains the 
following examples plus "show me" Help topics with step by step instructions.

Query by Form
  "Find a record based on a value you select from a list."
  "Find records based on values in one or more fields."
  "Show progressively more detail about a subject."
  "Use a custom function in a subform's SELECT statement."
  "User criteria from the main form to set the subform's RecordSource property."

Using Queries with Forms and Reports
  "Create a SELECT statement for a form based on user input."
  "Use a parameterized query in an event procedure."

The following articles also contain information and examples for building 
complex Query by Form solutions:
  Q93695  INF: Passing Values from a Form to a Parameter Query
  Q95931  INF: How to Use the Query by Form (QBF) Technique
  Q103181  INF: Showing All Records (Including Null) in a Parameter Query
  Q103252  INF: Query with Parameters to Evaluate Complex Criteria
  Q105522  INF: Using a Form Reference Parameter Query in Access Basic
  Q117544  INF: Query by Form (QBF) Using Dynamic QueryDef

Information and work-arounds for common problems encountered when 
designing and executing queries can be found in the following articles:
  Q116142  PRB: Update Query Based on Totals Query Fails
  Q119077  PRA: Error (-1310) Running Crosstab or Totalling Query  
  Q103429  PRB: "Out of Memory" or "Query Too Complex" Running Report    

If you have additional questions feel free to post them addressed to "All",  
in Section 3, Queries. 

Kim Hightower, Microsoft PSS
