MySQL根据where子句从具有相同字段的多个行中选择1个

Question

I need to be able to select my entire table but where there are duplicate id's, only select 1 of them based on the data in a different field.

For example if my table looks like this

I want to select all rows, but if there are 2 of the same id, select only the row with Billing as the address type.

Answer 1

You can do it this way:

select * from Table1 
where (AddressType='Billing') or
(AddressType='Shipping' and ID not in (select ID from Table1 where AddressType='Billing'))
order by ID

Explanation:

1st condition is to filter only Billing address types.

2nd condition is to filter Shipping address types which do not have Billing with the same ID.

Result in SQL Fiddle

Answer 2

Try this -

SELECT *, ADDRESS
FROM (SELECT MIN(ID), ADDRESSTYPE
      FROM YOUR_TABLE
      GROUP BY ADDRESS) X