Given the <b>Women</b> table: <PRE><CODE>+-----+--

Given the Women table:

+-----+-----------+-------+
|  Id | FirstName | Score |
+-----+-----------+-------+
|   1 | Angelina  |  500  |
|   2 | Paris     |    0  |
|   4 | Jennifer  | NULL  |
|   7 | Misha     | 3000  |
+-----+-----------+-------+

How many records will the following query return:


SELECT * FROM Women
WHERE Score >= ALL (SELECT Score
                    FROM Women
                    WHERE FirstName='Eva');

Query contains an error and will not be executed
0
1
2
3
4
7

Explanation

Whenever subquery is unable to return records, ALL operator automatically evaluates to True.

Theory

Logical Operators - Part1

Operator	Description
ALL	The ALL operator is used to compare a value to all values in another value set
AND	The AND operator allows the existence of multiple conditions in an SQL statement's WHERE clause
ANY	The ANY operator is used to compare a value to any applicable value in the list according to the condition
BETWEEN	The BETWEEN operator is used to search for values that are within a set of values, given the minimum value and the maximum value
EXISTS	The EXISTS operator is used to search for the presence of a row in a specified table that meets certain criteria

Logical Operators - Part2

Operator	Description
IN	The IN operator is used to compare a value to a list of literal values that have been specified
LIKE	The LIKE operator is used to compare a value to similar values using wildcard operators.
NOT	The NOT operator reverses the meaning of the logical operator with which it is used. Eg: NOT EXISTS, NOT BETWEEN, NOT IN, etc. This is a negate operator.
OR	The OR operator is used to combine multiple conditions in an SQL statement's WHERE clause.
IS	NULL The NULL operator is used to compare a value with a NULL value.
UNIQUE	The UNIQUE operator searches every row of a specified table for uniqueness (no duplicates)

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