sqlfriends (8/22/2012)

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I use the merge statement in a sproc to insert, update and delete records from a staging table to a production table.

In the long sql, here is a part of it,

When Matched and

((Student.SchoolID <> esis.SchoolID

OR

Student.GradeLevel <> esis.GradeLevel

OR

Student.LegalName <> esis.LegalName

OR

Student.WithdrawDate <> esis.WithdrawDate

Student.SPEDFlag <> esis.SPEDFlag

OR

Student.MailingAddress <> esis.MailingAddress)

Then update

Set Student.Schoolid=esis.schoolid,

.....

My question is how about if the column has null values in it.

for example

if schoolID is null in production table is null, but in staging table is not null, will the <> return true.

or if either side of <> has a null value, will it return true.

I don't want it to omit some records and causing the students records not get updated.

If not return true, how to fix this?

THanks