What are joins, explain all types of joins?
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Answer / Shivam Shukla
Joins in SQL allow the combination of rows from two or more tables based on a related column between them. There are several types of joins:
1. Inner Join: Returns only the matching rows from both tables involved in the join.
2. Left (Outer) Join: Returns all the rows from the left table and the matching rows from the right table, if any. If there is no match, null values are used for columns from the right table.
3. Right (Outer) Join: Returns all the rows from the right table and the matching rows from the left table, if any. If there is no match, null values are used for columns from the left table.
4. Full (Outer) Join: Returns all the rows when there is a match in either the left or right table. If there is no match, null values are used for columns from the non-matching table.
5. Cross Join (Cartesian Product): Returns the combination of every row from both tables involved in the join.
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