How to do an INNER JOIN on multiple columns

You can JOIN with the same table more than once by giving the joined tables an alias, as in the following example: SELECT airline, flt_no, fairport, tairport, depart, arrive, fare FROM flights INNER JOIN airports from_port ON (from_port.code = flights.fairport) INNER JOIN airports to_port ON (to_port.code = flights.tairport) WHERE...

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What is the difference between “INNER JOIN” and “OUTER JOIN”?

Assuming you're joining on columns with no duplicates, which is a very common case:An inner join of A and B gives the result of A intersect B, i.e. the inner part of a Venn diagram intersection.An outer join of A and B gives the results of A union B, i.e. the outer parts of a Venn diagram union.ExamplesSuppose you have two tables, with a...

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What is the difference between “INNER JOIN” and “OUTER JOIN”?

Assuming you're joining on columns with no duplicates, which is a very common case: An inner join of A and B gives the result of A intersect B, i.e. the inner part of a Venn diagram intersection. An outer join of A and B gives the results of A union B, i.e. the outer parts of a Venn diagram union. Examples Suppose you have two...

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Laravel 7: Adding where clause to a join condition

if you want add more condition on a join add more $join->on or $join->orOn.if you want to add a condition to your first select, add it outside join function.DB::table('users')->join('contacts', function($join){ $date = date('Y-m-d'); $join->on('users.id', '=', 'contacts.user_id');})->where('contacts.effective_date',...

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