![]() Get a final range and use the median of the range as the corresponding latitude or longitude. Select a range again based on the bit value and repeat the preceding steps. When the bit is 1, the point falls within the range on the right. When the bit is 0, the point falls within the range on the left. What should we do after obtaining the latitude and longitude bit strings?ĭivide the range in half each time. Next, starting from 0 in this bit string, connect the odd-position bits into a longitude code (0111110000000) and the even-position bits into a latitude code (101111001001). Use 5 bits to represent each of these five numbers. Steps for Converting Geohash Codes into Latitudes and Longitudesįirst, create a Base32 mapping table (assume that 32 characters are used for encoding).įor example, if the Geohash code is ezs42, it can be translated into 13, 31, 24, 4, and 2 according to the following table. For example, -180 and 180 indicate the same place, but they have completely different Geohash codes. In this case, wb12x represents a larger grid, and wb12xabcd represents a smaller grid. For example, wb12x comprises five characters, and it contains the grid wb12xabcd. A prefix always contains a range represented by longer code characters. Base36 geo encodings, which uses 36 characters for encoding, are also used in the industry.Īfter encoding, points close to each other have closer values. Geohash typically uses 32 characters for encoding. The size of the grid depends on the Geohash's precision. It is a hierarchical spatial data structure that divides space into buckets of a grid shape. What is Geohash? Working Mechanism of GeohashĪs defined by Oracle, Geohash is used for encoding latitude and longitude coordinates into a text string. ![]() Many databases chose Geohash technology in the early stages of development because PostGIS is more challenging to implement. However, not all databases use this technology. It is the most widely used technology with the highest precision and the best functionality. PostgreSQL PostGIS describes this type of information, including the altitude. Generally, we use latitudes and longitudes to represent locations on Earth. Multiple geographic representation methods are available in the industry.
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