[thelist] SQL : performance - separate table vs. (datatype) SET
Hassan Schroeder
hassan at webtuitive.com
Tue Nov 12 18:55:19 CST 2002
Paul Cowan wrote:
> Say you have the following tables:
> Recipe
> =======
> RecipeID RecipeName
> -------- ----------
> 1 Welsh Rarebit
> 2 Cheese Omelette
> 3 Cheese sandwich
> RecipeIngredient
> =================
> RecipeID IngredientName
> -------- --------------
> 1 Cheese
> 1 Bread
> 2 Cheese
> 2 Eggs
> 3 Cheese
> 3 Bread
> 3 Butter
> [1] SELECT RecipeID
> [2] FROM RecipeIngredient
> [3] WHERE
> [4] IngredientName IN ('Cheese', 'Bread')
> Note that you'd probably want a seperate 'ingredients' table,
OK, that's kind of a variation on my approach #1 -- but thats the
question: which is likely to be the most efficient?
Is joining the two tables on RecipeID with a WHERE looking at one
table (whether one column or multiple) going to be more or less
processor-intensive than the regex filtering LIKE "%Cheese%Bread%"
on a SET column?
Any ideas? Other than "it depends" and "try it!" which may be what
this comes down to... :-)
--
Hassan Schroeder ----------------------------- hassan at webtuitive.com
Webtuitive Design === (+1) 408-938-0567 === http://webtuitive.com
dream. code.
More information about the thelist
mailing list