How to call stored procedures in SQL

Syntax for calling stored procedures in SQL: CALL procedure_name(parameter1, parameter2, ...). The parameter type of stored procedures can be input, output, or input/output type, and the syntax is: CALL procedure_name(IN | OUT | INOUT parameter_name datatype). To get the value of the output parameter, use the @ symbol followed by the parameter name: SELECT @output_parameter_name;.

How to call stored procedures in SQL

Stored procedures are named blocks of SQL code precompiled and stored in a database. They are used to perform common or complex database operations, which can improve performance and code reusability.

Syntax for calling stored procedures

The syntax for calling stored procedures in SQL is as follows:

 <code class="sql">CALL procedure_name(parameter1, parameter2, ...);</code>

in:

• procedure_name is the name of the stored procedure to be called.
• parameter1 , parameter2 , ... are parameters to be passed to stored procedures.

Example

The following example calls a stored procedure named GetCustomerOrders , which requires a parameter customer_id :

 <code class="sql">CALL GetCustomerOrders(10);</code>

Pass parameter type

The parameters of the stored procedure can be of the following types:

• Input parameters: Used to pass values ​​to stored procedures.
• Output parameter: Used to return value from stored procedure.
• Input/output parameters: You can pass values ​​to stored procedures and return values ​​from stored procedures.

The syntax for passing parameter types is as follows:

 <code class="sql">CALL procedure_name(IN | OUT | INOUT parameter_name datatype);</code>

in:

• IN , OUT , INOUT Specifies the parameter type.
• parameter_name is the name of the parameter.
• datatype is the data type of the parameter.

Get the output parameter value

To get the value of the output parameter, use the @ symbol followed by the parameter name:

 <code class="sql">SELECT @output_parameter_name;</code>

Things to note

• The stored procedure name must exist in the current database or schema.
• The parameter list must match the parameter list in the stored procedure definition.
• The output parameter must be declared as OUT or INOUT in the stored procedure.
• Stored procedures can return multiple result sets.

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