SQL Join statement is used to combine data or rows from two or more tables based on a common field between them. Different types of Joins are as follows:
INNER JOIN LEFT JOIN RIGHT JOIN FULL JOIN
Reading a SQL join statement is not difficult. The most important thing to remember is that the tables are listed from left to right and the columns are listed from top to bottom.
When reading a SQL join statement, it is important to remember that the tables are listed from left to right and the columns are listed from top to bottom.
We should also keep in mind that when we specify which table we want, we should always use an alias for this table. This way, if there is more than one table with the same name, it will be clear which one we want.
For example:
SELECT * FROM Table1 AS t1 JOIN Table2 AS t2 ON t1.x = t2.y;
The SQL join statement is a powerful tool for joining data from two or more tables. It is used to combine rows of data from two tables that have a common column.
The result of the join is called a Cartesian product and can be very large when there are many rows in each table. The JOIN keyword tells the SQL engine which columns to match up and how to do it. There are four types of JOINs: INNER, LEFT OUTER, RIGHT OUTER, FULL OUTER JOIN.
An INNER JOIN returns all rows from both tables where there is at least one row in either table that has a matching value in the joined column(s). A LEFT OUTER JOIN returns all rows from the left table and only those rows
