sql - Select Row whose Column expression value is Valid

Question

I have a Table whose Column has an Expression as its Value. I want to write a Single Select Query to check if the Expression in that Column holds TRUE.

Here is My Table:

CREATE TABLE #TEMP (FinYear VARCHAR(9), TaxType VARCHAR(50), Rate NUMERIC(10,4), SlabExpression VARCHAR(50))  
INSERT INTO #TEMP  
VALUES ('2014-2015', 'SURCHARGE', 0.00, '#<=10000000'),  
       ('2014-2015', 'SURCHARGE', 10.00, '#>10000000'),  
       ('2014-2015', 'Education Cess', 3.00, '#<=10000000'),  
       ('2014-2015', 'Education Cess', 3.00, '#>10000000')  

SELECT * FROM #TEMP  
DROP TABLE #TEMP

My Income value now is 1200000 which obviously falls under the slab - '#>10000000' on which I intend to apply Surcharge and Education Cess rates.

But, How do I find the Correct Slab with a Single Query.

I know I can do that using a Cursor. But, I do not want to use a Cursor here. I need a Single Query.

Note: This Table has Two SlabExpression Values in one Column
ie. '#<=10000000' AND '#>10000000'

I want to Write a Single SELECT Query to get the two Rows for which the SlabExpression Holds True.
ie. I want the Result as the two Rows with SlabExpression '#>10000000'

Basically, I want a Query something Like

SELECT * FROM #TEMP WHERE SlabExpression Holds True

Answer 1

SELECT *, 
    CASE SUBSTRING(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression), PATINDEX('%[0-9]%', RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression))))
        WHEN '<=' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) <= CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) THEN 'True'
            ELSE 'False' END
        WHEN '=<' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) <= CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) THEN 'True'
            ELSE 'False' END
        WHEN '>=' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) >= CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) THEN 'True'
            ELSE 'False' END
        WHEN '=>' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) >= CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) THEN 'True'
            ELSE 'False' END
        WHEN '>' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) > CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) ) AS INT) THEN 'True'
            ELSE 'False' END
        WHEN '<' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) < CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) ) AS INT) THEN 'True'
            ELSE 'False' END
        WHEN '=' THEN 
            CASE WHEN CAST(LEFT(SlabExpression, PATINDEX('%[<,=,>]%', SlabExpression) -1) AS INT) = CAST(RIGHT(SlabExpression, LEN(SlabExpression) - PATINDEX('%[<,=,>]%', SlabExpression) ) AS INT) THEN 'True'
            ELSE 'False' END
        ELSE null
        END AS Value
 FROM #TEMP