Question

I think my where clause is wrong.

My dilemma is, if user don’t have a record in tbl_dentalBuyerInsurance that means they are taking all of it.

So if user don’t have a record in tbl_dentalBuyerInsurance I want them to come back as a result.
I also want them to come back if they do have a record in tbl_dentalBuyerInsurance and it matches using LIKE or equal.

SELECT
[dbo].[tbl_users].*, [dbo].[tbl_dentalBuyerInsurance].*
     FROM
[dbo].[tbl_users]
    LEFT OUTER JOIN [dbo].[tbl_dentalBuyerInsurance] ON [dbo].[tbl_dentalBuyerInsurance].buyerId = [dbo].[tbl_users].id
    LEFT OUTER JOIN [dbo].[tbl_dentalInsurance] ON [dbo].[tbl_dentalInsurance].id = [dbo].[tbl_dentalBuyerInsurance].dentalInsuranceId
    WHERE
(
    (
        [dbo].[tbl_dentalInsurance].companyName LIKE '%Cigna%'
        OR [dbo].[tbl_dentalInsurance].companyName = ''
    )
    AND(
        [dbo].[tbl_dentalBuyerInsurance].ppo = 1
        OR [dbo].[tbl_dentalBuyerInsurance].ppo = ''
    )
    AND(
        [dbo].[tbl_dentalBuyerInsurance].hmo = 0
        OR [dbo].[tbl_dentalBuyerInsurance].hmo = ''
    )
)

Answer 1

Given you’re using LEFT JOINS, if there’s no matching records on the “right” side of the join, all of those right-side fields will be NULL, not empty strings. You’d have to explicitly check for that with .... OR whatever IS NULL, as NULL cannot ever be equal to anything, including itself.