Syntax error in complex SQL Query condition - mysql

Question

I am having some trouble with my sql statement.
Here is a picture of the relevant tables:
A product can be in multiple categories.
A single product can have multiple varietycategories (ie: size, color, etc)
a varietycategory can have multiple varietycategoryoptions (ie: small, medium, large)
the table searchcriteria.criterianame loosly relates to varietycategory.category
the table searchcriteriaoption.criteriaoption loosely relates to varietycategoryoption.descriptor.
I get the searchcriteria.criterianame and use that string as the value we want to match with varietycategory.category and we also have to get the various searchcriteriaoption.criteriaoption strings (for that searchcriteria.criterianame) and match that against varietycategoryoption.descriptor for that varietycategory.category.
Here is the sql:
SELECT DISTINCT categories.*, product.*
FROM (categories, product, product_category)
LEFT JOIN varietycategory ON varietycategory.productid = product.id
LEFT JOIN varietycategoryoption ON varietycategoryoption.varietycategoryid = varietycategory.id
WHERE product_category.categoryid=4
AND product.id=product_category.productid
AND categories.category_id=product_category.categoryid
AND (
(varietycategory.category = 'color' AND (varietycategoryoption.descriptor='red' OR varietycategoryoption.descriptor='blue'))
OR
(varietycategory.category = 'size' AND (varietycategoryoption.descriptor = 'small' OR varietycategoryoption.descriptor='medium'))
)
but I get an error:
Unknown column 'varietycategory.id' in 'on clause'
I have tried to figure out what I am doing wrong. I tried simplifying the query a bit (just to try and determine what part of the sql query was causing the problem) to only match the searchcriteria.category string with the varietycategory.category and the query returns the data set correctly.
Here is the working query (this query is simplified and insufficient):
SELECT DISTINCT categories.*, product.*
FROM (categories, product, product_category)
LEFT JOIN varietycategory ON varietycategory.productid = product.id
WHERE product_category.categoryid=4
AND product.id=product_category.productid
AND categories.category_id=product_category.categoryid
AND (varietycategory.category = 'color' OR varietycategory.category = 'size' OR varietycategory.category='shape');
But I also need to be able to match against the varietycategoryoptions as well.
Just to avoid confusion, I am only using searchcriteria to get the field category and use it as a string to match against the varietycategory.category
and I am only using searchcriteriaoption to get the field criteriaoption and use it as a string to match against varietycategoryoption.descriptor
Does anyone know what I am doing wrong with my 1st query?
Please do help as SQL is not expertise.
Thank you!

Answer 1

The error is at:
OR
(varietycategory.category = 'size' (varietycategoryoption.desciptor = 'small' OR varietycategoryoption.descriptor='medium'))
^
|
An operator (AND, OR) is missing here
This has nothing to do with the join syntax, by the way.

Answer 2

Do not mix implicit and explicit joins. Your query should look like:
SELECT DISTINCT c.*, p.*
FROM product_category pc join
categories c
on c.category_id = pc.categoryid join
product p
on p.id = pc.productid join
varietycategory vc
ON vc.productid = p.id
WHERE c.categoryid = 4 AND
vc.category in ('color', 'size', 'shape');
You probably don't need the distinct, but that depends on the data. The left join is unnecessary because you are filtering on the second table in the where.
A simple rule: Never use commas in the from clause. To help, MySQL has scoping rules that can cause queries to break when you mix implicit and explicit join syntax.

Answer 3

The problem was a misspelled field on the table varietycategory, which I named
vcid, when I almost always name my table primary key id's "id".