The result of every SQL query is a table.

More Questions from Introduction to SQL

• The rows of the result relation produced by a SELECT statement can be sorted, but only by one column.
• The SQL keyword GROUP BY instructs the DBMS to group together those rows that have the same value in a column.
• ORDER BY can be combined with the SELECT statements.
• Each index consumes extra storage space and also requires overhead maintenance time whenever indexed data change value.
• To establish a range of values, < and > can be used.
• SQL provides the AS keyword, which can be used to assign meaningful column names to the results of queries using the SQL built-in functions.
• The condition in a WHERE clause can refer to only one value.
• If you are going to use a combination of three or more AND and OR conditions, it is often easier to use the NOT and NOT IN operators.
• The keyword BETWEEN can be used in a WHERE clause to refer to a range of values.
• COUNT(field_name) tallies only those rows that contain a value; it ignores all null values.

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