Create evaluate-boolean-expression.sql

Author: kamyu104

MySQL/evaluate-boolean-expression.sql

@@ -0,0 +1,13 @@
+# Time:  O(n)
+# Space: O(n)
+
+SELECT left_operand, operator, right_operand,
+       CASE WHEN operator = '>' AND v1.value > v2.value THEN 'true'
+            WHEN operator = '<' AND v1.value < v2.value THEN 'true'
+            WHEN operator = '=' AND v1.value = v2.value THEN 'true'
+            ELSE 'false' END AS value
+FROM expressions e
+LEFT JOIN variables v1
+ON e.left_operand = v1.name
+LEFT JOIN variables v2
+ON e.right_operand = v2.name;