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Mbtiles.Document

Returns a navigation table of the tiles and metadata in an MBTiles tileset.

Syntax​

Mbtiles.Document(
    source as binary,
    optional options as record
) as table

Remarks​

MBTiles is the standard single-file container for a map tileset, and like GeoPackage it is SQLite underneath. This function reads it without GDAL or a tile server.

The navigation table holds Metadata and Tiles entries, plus grids tables when the tileset carries UTFGrid data.

The Tiles table keeps zoom_level, tile_column and tile_row exactly as stored — which is TMS row order, per the MBTiles spec — and adds a computed tile_row_xyz column (2^zoom - 1 - tile_row) for XYZ/web-mercator consumers, because getting that flip wrong is the classic MBTiles bug.

Needs Sqlite3.Database

An MBTiles file is a SQLite database, so this reader calls Sqlite3.Database. If you are pasting the source, paste both and name the second query exactly Sqlite3.Database. PQDriverless.mez contains both already.

Options:

  • DecompressTiles : A logical (true/false), default null meaning auto. MBTiles vector tiles (format=pbf) are stored gzip-compressed; auto detects the gzip signature per tile and decompresses. True forces decompression and errors on a tile that isn't gzip; false leaves every tile untouched.
  • MaxRows : A number. Return at most this many tile rows.
  • Strict : A logical (true/false). When true, tolerated malformations become errors — a missing metadata table, or a gzip tile that fails to decompress (default is false).

Examples​

Example #1​

Read the tileset's metadata.

let
    Ts = Mbtiles.Document(File.Contents("C:\data\world.mbtiles"))
in
    Ts{[Name = "Metadata"]}[Data]

Example #2​

Count tiles per zoom level — a quick way to see how a tileset was built.

let
    Ts    = Mbtiles.Document(File.Contents("C:\data\world.mbtiles")),
    Tiles = Ts{[Name = "Tiles"]}[Data]
in
    Table.Group(Tiles, {"zoom_level"}, {{"Tiles", Table.RowCount, Int64.Type}})

Supported​

The plain tiles table layout (MBTiles 1.x); the deduplicated tippecanoe layout (map + images tables behind a tiles view, joined here in M); raster (png/jpg/webp) and vector (pbf) tile data; UTFGrid grids / grid_data tables when present. SQLite-level support and limits are those of Sqlite3.Database.

Not supported​

  • tiles views other than the map + images layout — clear error.

Integer cells decode exactly across the full signed 64-bit range, inherited from Sqlite3.Database; downstream M arithmetic may still coerce past 253.

Metadata​

Mbtiles.Metadata (the tileset's key-value pairs as a record), Mbtiles.Format, Mbtiles.Name.

Category​

Driverless connectors