1. difference between functions and stored procedures 2. What are triggers. 3. where is cross join used 4. question in which I had to use join 5. use and syntax for HAVING 6. Constraints 7. if a column accepts "m" and "f" only, how can you swap the values (Use of CASE)

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Accepted Answer

Answers to questions related to SQL concepts like functions, stored procedures, triggers, joins, and constraints.

Functions return a value while stored procedures do not.
Triggers are special types of stored procedures that are automatically executed in response to certain events.
Cross join is used to combine each row from one table with every row from another table.
Joins are used to combine data from two or more tables based on a related column.
HAVING is used to filter data based on aggregate functions like SUM or COUNT.
Constraints are rules that are enforced on the data in a table.
To swap values in a column that accepts 'm' and 'f' only, use a CASE statement to update the values.

Accepted Answer

Ans.1) The function must return a value but in Stored Procedure it is optional.

Ans.2) A trigger is a block of code that is executed automatically from a database statement. Triggers is generally executed for DML statement

Ans.3) It is based on cartesion method. Each row of one table will be mapped with every row of second table.

Ans.5) It applies filter on results which are generated by group by clause using specific aggregate functions. for example- Display the Duplicate Records--> select coloumn_name, count(*) from table name group by column_name having count(*)>1