Queries allow the user to extract relevant information from a database. So that instead of scanning the whole table, they can pre-define the categories of information which will be sought. Queries also allow the user to join multiple tables. For example, if you have a table called "customers" and a table called "invoices", you can use a query to join the two tables. When you run a query that joins these two tables, you can get results showing the name of the customer (from the customer table) and all associated invoices (from the invoices table). Queries are often used as the basis for reports in Access. Queries don't do the same things as any other part of a database, and so asking for their 'advantages' isn't really valid. They are the only way to extract some of a table's records while ignoring those which don't match the criteria set by the query.
You wants to print a single record in crystal report using vb6 but you don't where and how you write query to retreive single from database?
As you enter Visual Basics select windows form applications. Nameform, select single or multiple. After selecting what sort of formyou like to create proceed to link your contacts page or table todatabase. Apply filter query and select printer action.