PHP With MySQL & PostgreSQL: MySQL 8.0 GIS Units of Measure - Meter, foot, Clarke's yard, or Indian Foot

The ST_DISTANCE function has been upgraded in MySQL 8.0.16 to allow you to specify the unit of measure between to locations. Previously you had to convert from meters to what you desired but now you can use the INFORMATION_SCHEMA.ST_UNITS_OF_MEASURE table to help you get many of the more popular measurements (foot, yard, statue mile, nautical mile, fathom) and some ones that are new to me (chain, link, various feet). However some measures are omitted (furlong,smoot) that may have some relevance in your life.

select * from information_schema.ST_UNITS_OF_MEASURE;
Fetching table and column names from `mysql` for auto-completion... Press ^C to stop.
+--------------------------------------+-----------+---------------------+-------------+
| UNIT_NAME | UNIT_TYPE | CONVERSION_FACTOR | DESCRIPTION |
+--------------------------------------+-----------+---------------------+-------------+
| metre | LINEAR | 1 | |
| millimetre | LINEAR | 0.001 | |
| centimetre | LINEAR | 0.01 | |
| German legal metre | LINEAR | 1.0000135965 | |
| foot | LINEAR | 0.3048 | |
| US survey foot | LINEAR | 0.30480060960121924 | |
| Clarke's yard | LINEAR | 0.9143917962 | |
| Clarke's foot | LINEAR | 0.3047972654 | |
| British link (Sears 1922 truncated) | LINEAR | 0.20116756 | |
| nautical mile | LINEAR | 1852 | |
| fathom | LINEAR | 1.8288 | |
| US survey chain | LINEAR | 20.11684023368047 | |
| US survey link | LINEAR | 0.2011684023368047 | |
| US survey mile | LINEAR | 1609.3472186944375 | |
| Indian yard | LINEAR | 0.9143985307444408 | |
| kilometre | LINEAR | 1000 | |
| Clarke's chain | LINEAR | 20.1166195164 | |
| Clarke's link | LINEAR | 0.201166195164 | |
| British yard (Benoit 1895 A) | LINEAR | 0.9143992 | |
| British yard (Sears 1922) | LINEAR | 0.9143984146160288 | |
| British foot (Sears 1922) | LINEAR | 0.3047994715386762 | |
| Gold Coast foot | LINEAR | 0.3047997101815088 | |
| British chain (Sears 1922) | LINEAR | 20.116765121552632 | |
| yard | LINEAR | 0.9144 | |
| British link (Sears 1922) | LINEAR | 0.2011676512155263 | |
| British foot (Benoit 1895 A) | LINEAR | 0.3047997333333333 | |
| Indian foot (1962) | LINEAR | 0.3047996 | |
| British chain (Benoit 1895 A) | LINEAR | 20.1167824 | |
| chain | LINEAR | 20.1168 | |
| British link (Benoit 1895 A) | LINEAR | 0.201167824 | |
| British yard (Benoit 1895 B) | LINEAR | 0.9143992042898124 | |
| British foot (Benoit 1895 B) | LINEAR | 0.30479973476327077 | |
| British chain (Benoit 1895 B) | LINEAR | 20.116782494375872 | |
| British link (Benoit 1895 B) | LINEAR | 0.2011678249437587 | |
| British foot (1865) | LINEAR | 0.30480083333333335 | |
| Indian foot | LINEAR | 0.30479951024814694 | |
| Indian foot (1937) | LINEAR | 0.30479841 | |
| Indian foot (1975) | LINEAR | 0.3047995 | |
| British foot (1936) | LINEAR | 0.3048007491 | |
| Indian yard (1937) | LINEAR | 0.91439523 | |
| Indian yard (1962) | LINEAR | 0.9143988 | |
| Indian yard (1975) | LINEAR | 0.9143985 | |
| Statute mile | LINEAR | 1609.344 | |
| link | LINEAR | 0.201168 | |
| British yard (Sears 1922 truncated) | LINEAR | 0.914398 | |
| British foot (Sears 1922 truncated) | LINEAR | 0.30479933333333337 | |
| British chain (Sears 1922 truncated) | LINEAR | 20.116756 | |
+--------------------------------------+-----------+---------------------+-------------+
47 rows in set (0.0019 sec)

Monday, April 29, 2019

MySQL 8.0 GIS Units of Measure - Meter, foot, Clarke's yard, or Indian Foot