Question

I have a Complex SQL Query which is written with lot many Joins and Conditions.

ComplexQuery has few columns and most notable column names are WeightCode and DrugName.

[Assumption] : Select * from ComplexQuery.

I have a second Table : Select DrugName from Table2.

My requirement is such a way that,

If WeightCode = 2, Then First Five letters of DrugName from ComplexQuery matching First Five Letters of DrugName from Table 2 should be removed.

I am confused on approaching ..! How should i define in a single join query with filteration condition ??

Answer 1

Make use of Case..When may resolve your issue

Example

SELECT column1, column2
FROM TABLE
WHERE
column1 = 
  CASE @locationType
      WHEN 'val1' THEN column1
      WHEN 'val2' THEN column1 
  END

Note : this is just example