Lets assume table1 contains list of country names with columns translated to English and Spanish and table2 contains only some selected countries with only English column, I want to add Spanish column. Both tables contain id country code.
Table: countries1
code | country_english | country_spanish |
AL | Albania | Albania |
DZ | Algeria | Argelia |
AD | Andorra | Andorra |
AO | Angola | Angola |
Table: countries2
code | country_english | country_spanish |
AL | Albania | |
AO | Angola |
Result table:
code | country_english | country_spanish |
AL | Albania | Albania |
AO | Angola | Angola |
UPDATE countries2 SET `country_spanish` = (select `country_spanish` from countries1 where code = countries1.code)