Working with columns in a SELECT query

The goal of a SELECT query is to return a query result set that does the following:

At minimum, a SELECT query must specify one or more columns (or fields) to display in the query result set or to use for query criteria.

Other options for working with columns in a SELECT query include:

Setting a sort order for the results

For any column in your query, you can specify an ascending or descending sort order for the information returned in the query result set. This is especially important if the query properties are set to return only the TOP n or TOP n% of the information returned.
Adding criteria for a column

Setting criteria for a column ensures that only the desired records are returned in the query result set.
Introducing GROUP BY and aggregate functions

GROUP BY and aggregate functions allow the query to group data rows according to the values you specify and then calculate values such as the sum, maximum or minimum, average, or count for each group or for the entire table.
Hiding some columns or values

You may want to use a column in the criteria used to determine which records are returned, without actually displaying that column's information in the result set. You can do this by adding the column to the query and setting its criteria, and then hiding the column from the query result set.
Setting an alias for a column

If you find a column name to be long or complicated, you can set a simpler or abbreviated reference name – an alias – for the column. This only affects the column heading displayed in the query result set. An alias is also useful when you add a column to the query result set that contains calculated values instead of simply returning the contents of a field in the table.