The difference between mysql outer join and inner join query

The syntax for an outer join is as follows:

SELECT field name
FROM table name 1 LEFT|RIGHT|FULL| [OUTER] JOIN table name 2
ON table name 1. field name 1 = table 2. field name 2

Left Outer Join

The result set of the left outer join contains all records in the left table and the records in the right table that meet the join conditions. The column values ​​from the right table that do not meet the join conditions in the result set are null.

LEFT JOIN

Right Outer Join

A right outer join is the reverse of a left outer join. The result set of a right outer join includes all records in the right table and records in the left table that meet the join conditions. The column values ​​of the source and left tables that do not meet the join conditions in the result set are null.

Inner Join

The inner join query compares each row of table T1 with each row of table T2 and finds the combination that satisfies the join predicate. When the join predicate is satisfied, the matching rows in A and B are combined column-wise (side-by-side) into a single row in the result set.

Here are a few examples to explain in detail:

T1 table:

T2 table:

Inner join result:

SELECT T1.*,T2.*
FROM TI INNER JOIN T2
  ON A.Id=B.Id

Left join result:

SELECT T1.*,T2.*
FROM TI LEFT JOIN T2
  ON A.Id=B.Id

Right join result:

SELECT T1.*,T2.*
FROM TI RIGHT JOIN T2
  ON A.Id=B.Id

Summarize

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