Drop Constraint of a column(s) in SQL Server

How to drop particular(FK OR UQ OR DF) constraint based on given COLUMN_NAME in SQL Server?

Key Note: 
Generally you will come across this situation when you don't create CONSTRAINT NAME on your own.
When you asked to drop "only one unique constraints" on a column of a table(assume that table has 'n' unique constraints on other columns as well) for a particular column(or for a set of columns), how do you do it when all the constraint names are system generated?

--Input for a single column: TABLE_NAME & COLUMN_NAME  

DECLARE @TABLE_NAME VARCHAR(100) = 'TRANSACTION_PARCEL' 
DECLARE @COLUMN_NAME VARCHAR(100) = 'fromdate' 
DECLARE @SQL NVARCHAR(max) = '' 

SELECT @SQL += 'ALTER TABLE ' + @TABLE_NAME 
               + ' DROP CONSTRAINT ' + constraint_name + ';' 
FROM   information_schema.constraint_column_usage A 
       JOIN sys.objects B 
         ON A.constraint_name = B.NAME 
WHERE  --B.TYPE = 'UQ' AND  
  A.table_name = @TABLE_NAME 
  AND A.column_name = @COLUMN_NAME 
GROUP  BY A.constraint_name 

PRINT @SQL 

EXEC Sp_executesql 
  @SQL 


----Input for multiple columns: TABLE_NAME & COLUMN_LIST

DECLARE @TABLE_NAME VARCHAR(100) = 'TRANSACTION_PARCEL' 
DECLARE @SQL NVARCHAR(max) = '' 

SELECT @SQL += 'ALTER TABLE ' + @TABLE_NAME 
               + ' DROP CONSTRAINT ' + constraint_name + ';' 
FROM   information_schema.constraint_column_usage A 
       JOIN sys.objects B 
         ON A.constraint_name = B.NAME 
WHERE  --B.TYPE = 'UQ' AND  
  A.table_name = @TABLE_NAME 
  AND A.column_name IN ('PARCEL_BSKEY','TRAN_BSKEY','TRAN_PARCEL_BALANCE_TYPE') 
GROUP  BY A.constraint_name 

PRINT @SQL 

EXEC Sp_executesql 
  @SQL

Note: Code can be customized to pull out particular keys as well (F - foreign key, D - Default constraint, UQ - Unique constraint, PK - Primary Key constraint)

Before you drop constraint of type PK, you need to drop FK's which falls upon this PK.