CREATE TABLE "worked_example" (
  "geohash_length" real,
  "lat_bits" real,
  "lng_bits" real,
  "lat_error" text,
  "lng_error" text,
  "km_error" text
);

Question: What is the lowest geohash length when the lat bits are less than 7, and the km error of ±2500?
SQL: SELECT MIN("geohash_length") FROM "worked_example" WHERE "lat_bits"<7 AND "km_error"='±2500';

Question: What is the highest geohash length when the lat error is ±0.00068, and the lat bits larger than 17?
SQL: SELECT MAX("geohash_length") FROM "worked_example" WHERE "lat_error"='±0.00068' AND "lat_bits">17;

Question: What is the highest geohash length when there is a ng error of ±0.00017, and a lng bits smaller than 20?
SQL: SELECT MAX("geohash_length") FROM "worked_example" WHERE "lng_error"='±0.00017' AND "lng_bits"<20;