Problem
Table Variables:
+---------------+---------+ | Column Name | Type | +---------------+---------+ | name | varchar | | value | int | +---------------+---------+ In SQL, name is the primary key for this table. This table contains the stored variables and their values.
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Table Expressions:
+---------------+---------+
| Column Name | Type |
+---------------+---------+
| left_operand | varchar |
| operator | enum |
| right_operand | varchar |
+---------------+---------+
In SQL, (left_operand, operator, right_operand) is the primary key for this table.
This table contains a boolean expression that should be evaluated.
operator is an enum that takes one of the values ('<', '>', '=')
The values of left_operand and right_operand are guaranteed to be in the Variables table.
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Evaluate the boolean expressions in Expressions table.
Return the result table in any order.
The result format is in the following example.
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Example 1:
Input: Variables table: +------+-------+ | name | value | +------+-------+ | x | 66 | | y | 77 | +------+-------+ Expressions table: +--------------+----------+---------------+ | left_operand | operator | right_operand | +--------------+----------+---------------+ | x | > | y | | x | < | y | | x | = | y | | y | > | x | | y | < | x | | x | = | x | +--------------+----------+---------------+ Output: +--------------+----------+---------------+-------+ | left_operand | operator | right_operand | value | +--------------+----------+---------------+-------+ | x | > | y | false | | x | < | y | true | | x | = | y | false | | y | > | x | true | | y | < | x | false | | x | = | x | true | +--------------+----------+---------------+-------+ Explanation: As shown, you need to find the value of each boolean expression in the table using the variables table.