Question

I have two SQLite tables, recipes and ingredients. I need to find all of the recipes which have between 2 and 4 items from a list of ingredients but I can’t get my head round the SQL to make this work.

The tables are:

CREATE TABLE recipes (
    rowidx INTEGER  AUTOINCREMENT,
    RecipeID TEXT(10) NOT NULL PRIMARY KEY,
    Name TEXT(255) NOT NULL
);

 CREATE TABLE Ingredients (
    Recipe TEXT(10) NOT NULL PRIMARY KEY,
    Ingredient TEXT(255) NOT NULL COLLATE NOCASE,
    Measurement TEXT(255) NOT NULL
);

I started with something simple, but ran out of steam when I came to the ‘between n and n ingredients’ part.

SELECT COUNT(*) FROM Recipes 
WHERE RecipeID IN (
    SELECT Recipe FROM Ingredients WHERE Ingredient IN (milk','butter','sugar','flour','egg' ) 
) 

I’m sure there must be a relatively simple way to do this but it’s not clicking.

EDIT: I actually ended up with a modified version of the answer below:

SELECT *,ifnull((SELECT COUNT(i.Ingredient) AS IngredientCount FROM Recipes r LEFT JOIN Ingredients i ON r.RecipeID = i.Recipe WHERE i.Ingredient IN ('flour' ) and r.recipeid = allrecipes.recipeid GROUP BY R.RecipeID),0) AS IngredientCount 
FROM Recipes allrecipes
WHERE IngredientCount BETWEEN 2 AND 4

Unlike the original answer, if a recipe matches no ingredients, and BETWEEN 0 AND 2 is specified, it won’t even appear in the list for sorting, so will be excluded.

Answer 1

SELECT
    r.Name,
    COUNT(i.Ingredient) AS Ingredients
FROM
    recipes r
    LEFT JOIN ingredients i 
        ON i.Recipe = r.RecipeID
        AND i.Ingredient IN ('milk','butter','sugar','flour','egg')
GROUP BY r.Name
HAVING COUNT(i.Ingredient) BETWEEN 2 AND 4