Performance hint :
For static data, do not normalize too much.
For instance if you have a row which can be linked to several other rows, you can do this :
create table parents (
id serial primary key,
values... )create table children (
id serial primary key,
parent_id references parents(id),
integer slave_value )
Or you can do this, using an array :
create table everything (
id serial primary key,
integer[] children_values,
values... )Pros :
No Joins. Getting the list of chilndren_values from table everything is just a select.
On an application with several million rows, a query lasting 150 ms with a Join takes 30 ms with an array.
You can build the arrays from normalized tables by using an aggregate function.
You can index the array elements with a GIST index...
Cons :
No joins, thus your queries are a little bit limited ; problems if the array is too long ;
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