Question

I have this query

SELECT *, bp.product_id 
FROM builder_product as bp 
JOIN builder_step as bs 
    ON bs.builder_id=bp.builder_id  
JOIN builder as b 
    ON b.builder_id=bs.builder_id 
WHERE b.business_id = '60' 
GROUP BY product_id 
ORDER BY bs.step_number 

which is grabbing all the products from the builder_product table and all looks ok but on closer look the data is missing a few records and all the names are the same.

Here is the data and the schema and basically what I want is a query that gives me all the products from the builder_product table and the corresponding name from the builder_step table with the business_id of 60 from the builder table.

Any ideas what I am doing wrong and how to avoid duplicates?

Answer 1

It isn’t clear from your schema whether builder_product and builder_step are related by builder_id or by builder_step_id. If you clarify that I’ll modify the answer below.

You aren’t performing any aggregate functions (SUM(), COUNT(), AVG()) so you have no need for a GROUP BY. Instead you just have a couple of JOINs to perform:

SELECT
  bp.*,
  bs.name
FROM 
  builder_product bp
  JOIN builder_step bs ON bp.builder_step_id = bs.builder_step_id
  JOIN builder b ON bp.builder_id = b.builder_id
WHERE b.business_id = 60

The duplicates are a result of attempting to SELECT * without specifying a table name/alias. Instead, SELECT bp.*, bs.name indicates that specifically all columns from builder_product should be returned, plus the builder_name column from builder_step.