Call Statements

Syntax

Figure 1 shows the syntax diagram for calling a clause.

Figure 1 call_clause::=

The above syntax diagram is explained as follows:

procedure_name: specifies the name of a stored procedure.
parameter: specifies the parameters for the stored procedure. You can set no parameter or multiple parameters.

Examples

    
     
       
       
         -- Create a table.
gaussdb=# CREATE SCHEMA hr;
gaussdb=# SET CURRENT_SCHEMA = hr;
gaussdb=# CREATE TABLE staffs 
(
  section_id INTEGER, 
  salary INTEGER
);
gaussdb=# INSERT INTO staffs VALUES (30, 10);
gaussdb=# INSERT INTO staffs VALUES (30, 20);

-- Create the stored procedure proc_staffs.
gaussdb=# CREATE OR REPLACE PROCEDURE proc_staffs
(vIM
section     NUMBER(6),
salary_sum out NUMBER(8,2),
staffs_count out INTEGER
)
IS
BEGIN
SELECT sum(salary), count(*) INTO salary_sum, staffs_count FROM hr.staffs where section_id = section;
END;
/
CREATE PROCEDURE
-- Create the stored procedure proc_return.
gaussdb=# CREATE OR REPLACE PROCEDURE proc_return
AS
v_num NUMBER(8,2);
v_sum INTEGER;
BEGIN
proc_staffs(30, v_sum, v_num);  --Call a statement.
dbe_output.print_line(v_sum||'#'||v_num);
RETURN;  --Return a statement.
END;
/
CREATE PROCEDURE
-- Invoke the stored procedure proc_return.
gaussdb=# CALL proc_return();
30#2.00
 proc_return 
-------------

(1 row)

-- Delete the stored procedure.
gaussdb=# DROP PROCEDURE proc_staffs;
gaussdb=# DROP PROCEDURE proc_return;

--Create the function func_return.
gaussdb=# CREATE OR REPLACE FUNCTION func_return returns void
language plpgsql
AS $$
DECLARE
v_num INTEGER := 1;
BEGIN
dbe_output.print_line(v_num);
RETURN;  --Return a statement.
END $$;
CREATE FUNCTION

-- Call the function func_return.
gaussdb=# CALL func_return();
1
 func_return 
-------------

(1 row)

-- Drop the function.
gaussdb=# DROP FUNCTION func_return;

-- Clear the current database mode.
gaussdb=# DROP SCHEMA hr CASCADE;

        

      

    
   