SQL, VB, MicroStrategy & Other Topics

Use the following code to validate Social Security Number (USA). The rules used for validation are based on SSA website, Wikipedia and HowStuffWorks.com. There may be more rules to the validation. If you find any, keep me posted! 'njoy Validating! SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO -- ============================================= -- Author: Ankeet -- Create date: 6/19/2008 -- Description: Validates SSN -- ============================================= ALTER FUNCTION ValidateSSN ( @SSN varchar (11) ) RETURNS varchar (255) AS BEGIN /* USAGE: SELECT DBO.ValidateSSN(777992322) BASED ON: http://people.howstuffworks.com/social-security-number2.htm http://en.wikipedia.org/wiki/Social_Security_number http://www.socialsecurity.gov/employer/stateweb.htm http://en.wikipedia.org/wiki/Individual_Taxpayer_Identification_Number The Administration publishes the last group number used for each area number.[17]. Since group numbers are allocated in a regular (if unusual) pattern, it i...

CHECKSUM will calculate a hash value for the provided function parameters. CHECKSUM function when run multiple times for the same parameters, will result in same hash value. But it is not guaranteed that supplying different parameters will always result in a different hash. Therefore using CHECKSUM to uniquely identify each column of a table is not recommended (even with primary keys implemented on the table). I use this function to see if there were changes to any columns in a given row. Each of my tables have an additional column called ChecksumValue with INT datatype. Periodically (nightly in my case) I calculate Checksum for each row and compare it with the ChecksumValue column and if they turn out to be different, take appropriate action (send out email / restore original value etc). CREATE TABLE Example( FName varchar (50), LName varchar (50), ChecksumValue int ) -- Initially: UPDATE Example SET ChecksumValue = CHECKSUM (FName, LName) -- or CHECKSUM(FName) to track changes to ...