在Oracle中，当插入表时如何处理NULL值

Question

I have one table, which has a filed. When I insert in that table with the Empty value like '' or null, it should get converted to 'DUMMY-VALUE'.

--Have one table;
CREATE TABLE TEST  ( FIELD1 VARCHAR2(50) );

--When I insert ''
INSERT INTO TEST(FIELD1) VALUES('');

SELECT * FROM TEST
--Expected Result 'DUMMY-VALUE' but not NULL

I can apply NVL('','DUMMY-VALUE') in INSERT statement but I am allowed to change CREATE statement only. For Now, I am handing this with TRIGGER but , wondering if there is any alternative in 11g however I know about DEFAULT ON NULL for oracle 12c.

Answer 1

You can do like this:

create table TEST  (FIELD1 VARCHAR2(50) default 'DUMMY-VALUE'  );

and when you want to insert you should insert without that field if the values is NULL or empty

Answer 2

Try this:

CREATE TABLE TEST (FIELD1 VARCHAR2(50) DEFAULT 'DUMMY-VALUE');

then use the DEFAULT keyword in the INSERT statement:

INSERT INTO TEST (FIELD1) VALUES (DEFAULT);

SQLFiddle here

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