Queries Explained
Queries are used to analyse data in a database. They can take many different forms depending on what they need to do.The query does not work with a copy of the data – it deals with a dyna set, which comes from the expression dynamic subset. The data can be selected against a criteria that is specified. As the data in the tables change, then so can the answers to the query.
The query can also be used to display particular fields rather than all of the fields in a table. The fields can come from one table, several tables, another query or a combination of tables and queries.
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