Dear Monks,
Apologies for being off-topic but I come here seeking advice as I know the depth of experience in the monastery (and everything else in the project is built with Perl).

I am creating a database for a heritage organisation who try to keep alive 100s of varieties of heirloom apple trees - the ones we will need when the climate goes really crazy!

The tree table has a number of fields like:

usage
origin
flowering
ripe
picking
status
rootstock
is_triploid
[download]

Some of these fields can have multiple values, so to store them in an index I intend to create extra tables. I have come up with two options but am unsure which to choose.

Option 1
Create a table for each field:

CREATE TABLE tree_usage_index (
    id int,
    name varchar(100),
    PRIMARY KEY (name,id)
);
CREATE TABLE tree_flowering_index (
    id int,
    name varchar(100),
    PRIMARY KEY (name,id)
);
[download]

The problem I have with this set up is that to do a search for

trees with usage of 'cider' or usage of 'juicer' and with flowering of 'spring' and with ripe of 'autumn'

I will have to query multiple tables, and the code I have written for this seems a bit complex.

SELECT id from tree_usage_index WHERE name='cider' OR name='juicer'
# if there are results
SELECT id from tree_flowering_index WHERE id IN (results) and name='sp
+ring'
# if there are still results
SELECT id from tree_ripe_index WHERE id IN (results) and name='autumn'
[download]

I know you can nest SQL selects but as there are 12 fields that could be involved in a query the SQL could get a bit hairy. Also, I will probably need to add an index to the 'id' field of each table to speed up the WHERE id IN (results)

Option 2
Create one table for all fields:

CREATE TABLE tree_field_index (
    field varchar(100),
    id int,
    name varchar(100),
    PRIMARY KEY (field,name,id),
);
[download]

The advantage I see with this is that I will only need to query the one table to perform the same search:

SELECT id from tree_field_index WHERE ( (field='usage' AND name='cider
+') OR (field='usage' AND name='juicer') ) AND (field='flowering' AND 
+name='spring') AND (field='ripe' AND name='autumn')
[download]

Any advice on the right path to take, or some other solution, greatly appreciated.

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