The LEAST function in postgreSQL is used to find the least (smallest) value among a list of expressions. It takes multiple arguments and returns the minimum value from those arguments. The syntax of the LEAST function is as follows: LEAST(expression1, expression2, …, expressionN) Here’s an example of how the LEAST function can be used: SELECT…

In PostgreSQL, the GREATEST function is used to find the greatest (largest) value among a list of expressions. It takes multiple arguments and returns the maximum value from those arguments. The syntax of the GREATEST function is as follows: GREATEST(expression1, expression2, …, expressionN) Here’s an example of how the GREATEST function can be used: SELECT…

The NULLIF function is used to compare two expressions and return NULL if they are equal, otherwise it returns the first expression. This function is often used to handle situations where you want to avoid having a particular value and replace it with NULL based on a condition. The syntax of the NULLIF function is…

The COALESCE function is used to return the first non-null expression from a list of expressions. It’s often used to provide a default value when dealing with nullable columns or expressions. If the first expression in the list is not NULL, the COALESCE function will return that expression; otherwise, it will return the first non-null…

The CASE statement in PostgreSQL is used to perform conditional logic within a query. It allows you to create conditional expressions that produce different results based on specified conditions. There are two forms of the CASE statement in PostgreSQL: the simple CASE and the searched CASE. SELECT column_name, CASE column_name WHEN value1 THEN result1 WHEN…