SQL design and / or PHP class for storing dynamic two-dimensional arrays?

Question

I need an elegant way to store dynamic arrays (basically spreadsheets without all the functionality) of various sizes (both x and y), mostly being used as ENUMs, lists, lookup data, price sheets, that sort of thing. Multi-lingual would be a great bonus. Speed of the essence.

Here's an example of a typical "sheet" ;

            |  1 |  2 |   3 |   4
  -------------------------------
  model A   | 2$ | 5$ |  8$ | 10$
  model B   | 3$ | 6$ |  9$ | 12$
  model C   | 4$ | 8$ | 10$ | 13$

So, to get info, I would do ;

  $price = this_thing_im_after ( '3', 'model B' ) ;
  echo $price ;   // Prints '9$'

I'm in the PHP5 and Zend Framework world, but thoughts on design and SQL is just as dandy, even suggestions on and from the outside world, libs, extensions, etc. as I don't want to reinvent too much of the wheel. I need the backend stuff the most, and I'll write a GUI for dynamic sheets later. Thoughts, ideas, pointers?

Just an edit to point out that I'd prefer not to serialize and blob the data as I would like to query the indeces and sheets, perhaps even the data (or type for those who support such, now that would be awsome!) if I'm in a crazy mood. But again, this is not a breaker for me; if someone has a nice library or class for serializing in and out quickly out of a database with some simple querying, I'm all happy.

Answer 1

Is there any need to fetch only part of a spreadsheet, or query by contained data?

If you just want to store and retrieve the whole thing, I would just use an unambiguous textual representation of the array (e.g. serialize()) and store it as TEXT.

Answer 2

Other than serializing the whole thing into a blob field, you probably end up with a key/value table where your key is the row and col fields:

  CREATE TABLE sheet (
      sheet_id int not null,
      name varchar(32),
      rows int, -- stores max dimension if needed
      cols int, -- stores max dimension if needed
      primary key (sheet_id)
  );
  CREATE TABLE cells (
      cell_id identity, -- auto inc field for ease of updates
      sheet_id int not null, -- foreign key to sheet table
      row int not null,
      col int not null,
      value smalltext, -- or a big varchar depending on need
      primary key (cell_id), -- for updates
      unique index (sheet_id, row, col), -- for lookup
      index (value) -- for search
  );

  CREATE TABLE row_labels (
      sheet_id int not null,
      row int not null,
      label varchar(32),
      primary key (sheet_id, row)
  );

  CREATE TABLE col_labels (
      sheet_id int not null,
      col int not null,
      label varchar(32),
      primary key (sheet_id, col)
  );

This allows you to slice the data nicely:

 // Slice [4:20][3:5]
 SELECT row, col, value FROM cells
 WHERE sheet_id = :sheet
   AND row BETWEEN 4 AND 20
   AND col BETWEEN 3 AND 5
 ORDER BY row, col

 while ($A = fetch()) {
     $cell[$A['row'][$A['col']] = $A['value']; // or unserialize($A['value']);
 }