oracle11g - Oracle query to get the results of a particular table using the result obtained from another table -


i new oracle, kindly bear me if question sounds naive.

so, have 2 tables tablea , tableb have 2 columns id, name simplicity.

i want id value particular value of name in tablea. if requirement, query suffice - 

select id tablea name = 'some_name';

now, want take id , delete rows in tableb match id-

delete tableb id = <id obtained above query>;

what composite query in oracle perform function?

thanks!

if know single id value going returned particular name value, you'd do

delete tableb b  b.id = (select a.id                  tablea                 a.name = 'some_name')

note aliases optional. however, adding aliases makes things clearer no 1 has guess id or name you're referring @ point.

if there might multiple id values in tablea given name, you'd use in rather =

delete tableb b  b.id in (select a.id                   tablea                  a.name = 'some_name')

this work if knew query against tablea going return 1 row. i'd prefer equality query if you're sure 1 row returned, though. i'd rather error if expectations violated rather potentially having unexpected rows deleted.


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