gsi-cyberjapan/daicho-spec

Specifications for GSI Tile Daicho

[WIP] daicho-spec

Specifications for GSI Tile Daicho

What is GSI Tile Daicho?

A GSI Tile Daicho is an SQLite3 database to accelerate the production of GSI Tile List (mokuroku.csv.gz). Daicho works as a cache of the Mokuroku metadata.

Database design

Overview

• location: same as each mokuroku.csv.gz
• file name: daicho.sqlite3
• table name: cache

Table design

In Sequel, the table design will be described as the following:

$db = Sequel.sqlite('daicho.sqlite3')
unless $db.tables.include?(:cache)
  $db.create_table :cache do
    primary_key String :zxy
    index :zxy, :unique => true
    String :md5
    Integer :mtime
    Integer :size
    Integer :z
    index :z
    Integer :x
    index :x
    Integer :y
    index :y
  end
end

The extension of the file must be stored outside of the database to generate path of the tile. The extension of the file is typically stored in layers.txt.

See Also

See also the database design of client (downloader) side cache md5sum_cache.sqlite3 used in qdltc.rb.

Initialzing Daicho from Mokuroku

init_daicho(mokuroku_in, daicho_path, ext)

will be run for each tile dataset.

See daicho-init for implementation.

Update Daicho from the filesystem

update_daicho(daicho_path, tileset_path, ext)

will be run for each tile dataset.

See daicho-update for implementation.

Export Mokuroku from Daicho

export_mokuroku(daicho_path, mokuroku_out, ext)

will be run for each tile dataset.

See daicho-export for implementation.