A FULL OUTER JOIN is used to retrieve data from two or more tables based on a specified condition, including all rows from both the left (or first) table and the right (or second) table. If there’s no match for a row in one table, the columns from the other table will be filled with…

A self-join in PostgreSQL is a type of join operation where a table is joined with itself. This is often used when you have a single table that contains related data that you want to compare or analyze within the same table. To perform a self-join, you treat the table as if it were two…

A RIGHT JOIN is used to retrieve data from two or more tables based on a specified condition, while also including all the rows from the right (or second) table, even if there is no match in the left (or first) table. This means that even if there is no matching row in the left…

A LEFT JOIN is used to retrieve data from two or more tables based on a specified condition, while also including all the rows from the left (or first) table, even if there is no match in the right (or second) table. This means that even if there is no matching row in the right…

The INNER JOIN operation is used to retrieve records that have matching values in both tables being joined. It combines data from two or more tables based on a common column, and it only includes rows where there is a match in both tables. The basic syntax of an INNER JOIN is as follows: SELECT…

The INTERSECT operator is used to retrieve the common rows between the result sets of two or more SELECT queries. It returns only the distinct rows that are present in all specified queries. Unlike UNION and UNION ALL, the INTERSECT operator doesn’t include duplicate rows. The basic syntax of the INTERSECT operator is as follows:…

The UNION ALL operator is used to combine the result sets of two or more SELECT queries into a single result set, including all rows, even if there are duplicates. Unlike the regular UNION operator, UNION ALL does not remove duplicate rows from the combined result. The basic syntax of the UNION ALL operator is…

The UNION operator is used to combine the result sets of two or more SELECT queries into a single result set. The UNION operator removes duplicate rows from the combined result by default. If you want to include duplicate rows, you can use the UNION ALL operator. The basic syntax of the UNION operator is…

The ALL clause is typically used in conjunction with comparison operators to compare a value against all values in a set returned by a subquery.The ALL clause returns TRUE if the condition is satisfied for all values in the set. Here’s the basic syntax of using the ALL clause: SELECT columns FROM table_name WHERE expression…

The ANY clause is used to compare a value with a set of values returned by a subquery. It’s often used in combination with other comparison operators to check if a value matches any value within a set. The ANY clause returns TRUE if the condition is satisfied for at least one value in the…