Stored Procedure and Function have different properties. They have certain limitations, and the result is different in both cases. Stored Procedure needs both input and output parameters, but there is no need for output parameters in Function. The function can be called by using stored procedure, but the opposite way is not possible.
Stored Procedure vs Function
The main difference between Stored Procedure and Function is Function will always give the output, but Stored Procedure can sometimes produce no result. The input and output information has to be mentioned in Stored Procedure, but it is not like this in Function. The Function only needs an input parameter. Stored Procedure can produce a big value which can be up to 1024 values, but a Function will return only one particular value.
Stored Procedures are normally called independently. The execute command helps to call the stored procedure independently. This cannot be called from functions. It helps to call the functions. Functions can be invoked from the stored procedure. The stored procedure can return 1024 values as a result.
The function does not need any specific output parameter. It only requires input parameters to produce the result. It does not invoke multiple results. Rather it produces only one result. A function can be written and embedded within a SELECT statement. It will always produce the result. The result is only one value and a particular value.
Comparison Table Between Stored Procedure and Function
| Parameters of Comparison | Stored Procedure | Function |
| Requirements | Input and output parameter | Input parameter |
| Result | Multiple large values | Single result |
| Invoked by | None | Stored procedure |
| Return value size | 1024 digits | 1 digit |
| Probability of output | Moderate | High |
| Modification of data | Yes | No |
What is Stored Procedure?
The operation of the Stored Procedure does not depend on anything. Rather it is independently working and produces the result. It is generally used to invoke functions. It depends on the Stored Procedure that it will produce the result or not. Sometimes there is no result, and sometimes there are multiple results.
Stored Procedure needs input and output parameters both to produce the result. The Stored Procedure cannot work in some cases like it cannot work under having, select, or where statements. The data which is used in the Stored Function can be modified at any point in time. These are generally pre-compiled objects.
Pre-compiled objects were compiled for the first time, and the system remembers the format of the data. These formats are useful when other things are compiled by the users. The values keep on changing. The result can be a very large value or small value and sometimes no value at all.
This reduces the server traffic as it generally reduces the SQL queries into a small line, due to which transmission is faster. It even reduces the development cycle. The work can be done in very little time. It is easily used by multiple users as it is a stored procedure.
What is Function?
Functions are generally divided into two categories which are user-defined functions and built-in functions. Built-in functions are already present in the SQL server, whereas User-defined functions have to be declared by the users in SQL functions. It needs input parameters, and there is no need for output parameters.
It always produces a particular value. The execution of codes becomes faster by using these user-defined functions. The formats are already there, due to which compilation of codes becomes easy, and there is no time-consuming process. The execution becomes faster as the formats are used continuously for execution.
There is no possibility of returning a null value. It will always return a particular value. These functions cannot call user-defined functions. Functions can be invoked by using select statements in the SQL server. In this type of function, UDF is used in the result set within the join clause.
Functions cannot make use of try-catch blocks. It does not need an output parameter to produce the result. There is no requirement of output parameters in the functions. DML statements cannot be used in SQL, but select statements can be easily used in these types of servers.
Main Differences Between Stored Procedure and Function
- Stored Procedure needs both input and output parameters, but Function needs only input parameter.
- Stored Procedure return multiple result but Function never returns multiple answers.
- A stored procedure cannot be invoked from the function, but a function can be invoked from the Stored Procedure.
- Stored Procedure can return 1024 values at once, but Function will give only one value as a result.
- Stored Procedure can sometimes not answer, but Function will always give the output.
- Data can be modified in Stored Procedure but not in Function.
Conclusion
The values keep on changing. The result can be a very large value or a small value. Stored Procedure can return 1024 values. It depends on the Stored Procedure that it will produce the result or not. It even reduces the development cycle. Stored Procedure returns multiple results.
The Stored Procedure cannot work in some cases like it cannot work under having, select, or where statements. Stored Procedure needs both input and output parameters. It is independently working and produces the result. Pre-compiled objects were compiled for the first time, and the system remembers the format of the data.
The formats are already there, due to which compilation of codes becomes easy, and there is no time-consuming process. The function will always give the output. . Functions can be invoked by using select statements in the SQL server. Built-in functions are already present in the SQL server, whereas User-defined functions have to be declared by the users in SQL functions.
There is no requirement of output parameters in the functions. A function can be invoked from the Stored Procedure. In this type of function, UDF is used in the result set within the join clause. The function will always give the output.
References
- http://sutiawan.staff.gunadarma.ac.id/Downloads/files/32426/SQL+Server+2000+Stored+Procedure+Programming.pdf
- https://dl.acm.org/doi/abs/10.5555/1083592.1083734