Shulou(Shulou.com)06/01 Report--

This article mainly introduces how to achieve mbtiles data merging in GIS development, has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, the following let the editor take you to understand it.

Mbtiles is a sqlite database, which is used to store sliced map data according to a certain organizational format. It is often used in map packages of stand-alone and mobile terminals. In the release of map data, compared with direct sliced file data, it is unified in storage and easy to move and copy.

After the data downloaded through the Internet is converted into mbtiles, it is found that the data is not enough and needs to be downloaded again. When downloading, the previous data needs to be downloaded again. For high-level slices, the download time is still very slow.

Mbtiles itself is a sqlite database, which can be developed through development languages such as java, C #, etc., so you can merge two or more mbtiles data through development.

The following figure shows the table structure of the mbtiles file:

Metadata is some common information of slicing, map is the index information of slicing, images is the specific storage of sliced file data, and the picture is stored in the database with binary information.

In the merger of mbtiles, the bounds information in metadata needs to take the maximum range according to the files of each mbtiles, or calculate the maximum range according to several mbtiles. If the scope is not enough, the data can not be accessed comprehensively after release.

When merging, it is necessary to compare the index information in map and judge according to the combination of zoom_level, tile_column and tile_row. If there is data, it does not need to be written, and the data that does not exist is first written into the table. In the guid of generating tile_id, in the images table, the combination of the generated guid and sliced pictures is written into the table, so as to achieve the effect of data merging.

Thank you for reading this article carefully. I hope the article "how to merge mbtiles data in GIS Development" shared by the editor will be helpful to everyone. At the same time, I also hope that you will support and pay attention to the industry information channel. More related knowledge is waiting for you to learn!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.