Oracle function creation and invocation

definition of the function:

CREATE OR REPLACE FUNCTIONFunction_test (PARAMER1inch VARCHAR,--the type of the parameter does not write length PARAMER2 outVARCHAR, PARAMER3inch VARCHAR)  RETURN VARCHAR--function to write return value
As--Indicates the beginning of the function bodyPARAMER4VARCHAR( +); --Define internal parameters PARAMER5VARCHAR( +);BEGINPARAMER4:=CONCAT (PARAMER1, PARAMER3); --the assignment symbol is: = PARAMER5:=CONCAT (PARAMER3, PARAMER1); PARAMER2:=CONCAT (PARAMER4, PARAMER5); RETURN 'SUCCESS';End [Function_test]; --the function name after end can be omitted

Execute code: SQL> varPARAMER2varchar2SQL> varYvarchar2SQL> exec: Y:=Function_test ('123',:P ARAMER2,'ASD'); Results: PL/Sqlproceduresuccessfully completedy---------SUCCESSPARAMER2---------123

Oracle function creation and invocation