What is the difference between a select query and an update query in Microsoft Access?

In Microsoft Access, a select query and an update query serve different purposes in the context of working with a database.

1. **Select Query:**
   - A select query is used to retrieve data from one or more tables in a database. It allows you to specify the criteria for selecting records and define the fields that should be included in the result set. The primary purpose of a select query is to fetch and display information without modifying the data in the tables.

   - Example of a select query:
     ```sql
     SELECT FirstName, LastName, City
     FROM Customers
     WHERE Country = 'USA';
     ```

   - This query retrieves the first name, last name, and city of customers from the "Customers" table where the country is 'USA'.

2. **Update Query:**
   - An update query, on the other hand, is used to modify existing records in a table. It allows you to change the values of one or more fields based on specified criteria. The primary purpose of an update query is to make changes to the data stored in the tables.

   - Example of an update query:
     ```sql
     UPDATE Products
     SET Price = Price * 1.1
     WHERE Category = 'Electronics';
     ```

   - This query increases the prices of products in the "Products" table by 10% for items in the 'Electronics' category.

In summary, the key difference between a select query and an update query in Microsoft Access lies in their purpose:

- **Select Query:** Retrieves and displays data from one or more tables without modifying the data.

- **Update Query:** Modifies existing records in a table based on specified criteria.

It's important to use each type of query appropriately based on the task at hand to ensure the integrity of your data and achieve the desired results. Always exercise caution when using update queries to avoid unintended changes to your database.