sql - how to find people with same family name? -

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you have table 4 columns:

primary key / name / surname / middle name

how write sql query find people has same family name?

1 / ivan / ivanov / ivanovich

2 / petr / levinsky / aleksandrovich

3 / alex / ivanov / albertovich

should return ivan , alex

thanks

in standard sql can join table itself:

select a.name, b.name t a, t b a.surname = b.surname , a.id < b.id

where t table , id primary key column.

this returns distinct pairs of first names every surname has multiple entries.

you might want add surname list of selected columns.


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