Oracle PL/SQL Tutorial/PL SQL Data Types/Data Type Conversion
Datatype Conversions: Implicit Conversion
<source lang="sql">
SQL> SET SERVEROUTPUT ON SQL> SQL> DECLARE
2 d1 DATE; 3 cd1 VARCHAR2(10); 4 cd2 VARCHAR2(10); 5 n1 NUMBER; 6 c_cn1 VARCHAR2(10); 7 c_cn2 VARCHAR2(10); 8 BEGIN 9 cd1 := "15-Nov-99"; 10 d1 := cd1; 11 cd2 := d1; 12 DBMS_OUTPUT.PUT_LINE("CD1 = " || cd1); 13 DBMS_OUTPUT.PUT_LINE("CD2 = " || cd2); 14 c_cn1 := "995"; 15 n1 := c_cn1 + .99 ; 16 c_cn2 := n1; 17 DBMS_OUTPUT.PUT_LINE("c_cn1 = " || c_cn1); 18 DBMS_OUTPUT.PUT_LINE("c_cn2 = " || c_cn2); 19 END; 20 /
CD1 = 15-Nov-99 CD2 = 15-NOV-99 c_cn1 = 995 c_cn2 = 995.99 PL/SQL procedure successfully completed. SQL></source>
Explicit Conversion
Oracle has several built-in functions that are designed to convert information from one datatype to another.
Conversion functions.
Function Purpose TO_DATE Converts a character string to a date TO_NUMBER Converts a character string to a number TO_CHAR Converts either a number or a date to a character string