mysql - SQL help - Updating a field in one table to match a field in another table based on matching a different field -


appreciate help. i'm working on db designed bit poorly. need fix bad data updating 1 table based on follows (i loosely describing sql need):

two tables:

  • airports - includes fields: lat, lon, airport_id.
  • events - includes fields: lat, lon, airport_id.

i want update (currently incorrect) events table lat , lon (correct) airports table lat , lon.

basically: update events <events.airport_id = airports.airport_id> set events.lat = airports.lat

then can run again lon.

i know i'm close, not there exact syntax.

thanks!

this should work:

update events e set    e.lat = (select a.lat airports a.airport_id = e.airport_id),        e.lon = (select a.lon airports a.airport_id = e.airport_id) ;

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