insert multiple row into table using select however table has primery key in oracle SQL [duplicate] - oracle

Question

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How to create id with AUTO_INCREMENT on Oracle?
(18 answers)
Closed 8 years ago.
I am facing issue while inserting multiple row in one go into table because column id has primary key and its created based on sequence.
for ex:
create table test (
iD number primary key,
name varchar2(10)
);
insert into test values (123, 'xxx');
insert into test values (124, 'yyy');
insert into test values (125, 'xxx');
insert into test values (126, 'xxx');
The following statement creates a constraint violoation error:
insert into test
(
select (SELECT MAX (id) + 1 FROM test) as id,
name from test
where name='xxx'
);
This query should insert 3 rows in table test (having name=xxx).

Answer 1

You're saying that your query inserts rows with primary key ID based on a sequence. Yet, in your insert/select there is select (SELECT MAX (id) + 1 FROM test) as id, which clearly is not based on sequence. It may be the case that you are not using the term "sequence" in the usual, Oracle way.
Anyway, there are two options for you ...
Create a sequence, e.g. seq_test_id with the starting value of select max(id) from test and use it (i.e. seq_test_id.nextval) in your query instead of the select max(id)+1 from test.
Fix the actual subselect to nvl((select max(id) from test),0)+rownum instead of (select max(id)+1 from test).
Please note, however, that the option 2 (as well as your original solution) will cause you huge troubles whenever your code runs in multiple concurrent database sessions. So, option 1 is strongly recommended.

Answer 2

Use
insert into test (
select (SELECT MAX (id) FROM test) + rownum as id,
name from test
where name='xxx'
);
as a workaround.
Of course, you should be using sequences for integer-primary keys.

Answer 3

If you want to insert an ID/Primary Key value generated by a sequence you should use the sequence instead of selecting the max(ID)+1.
Usually this is done using a trigger on your table wich is executed for each row. See sample below:
CREATE TABLE "MY_TABLE"
(
"MY_ID" NUMBER(10,0) CONSTRAINT PK_MY_TABLE PRIMARY KEY ,
"MY_COLUMN" VARCHAR2(100)
);
/
CREATE SEQUENCE "S_MY_TABLE"
MINVALUE 1 MAXVALUE 999999999999999999999999999
INCREMENT BY 1 START WITH 10 NOCACHE ORDER NOCYCLE NOPARTITION ;
/
CREATE OR REPLACE TRIGGER "T_MY_TABLE"
BEFORE INSERT
ON
MY_TABLE
REFERENCING OLD AS OLDEST NEW AS NEWEST
FOR EACH ROW
WHEN (NEWEST.MY_ID IS NULL)
DECLARE
IDNOW NUMBER;
BEGIN
SELECT S_MY_TABLE.NEXTVAL INTO IDNOW FROM DUAL;
:NEWEST.MY_ID := IDNOW;
END;
/
ALTER TRIGGER "T_MY_TABLE" ENABLE;
/
insert into MY_TABLE (MY_COLUMN) values ('DATA1');
insert into MY_TABLE (MY_COLUMN) values ('DATA2');
insert into MY_TABLE (MY_ID, MY_COLUMN) values (S_MY_TABLE.NEXTVAL, 'DATA3');
insert into MY_TABLE (MY_ID, MY_COLUMN) values (S_MY_TABLE.NEXTVAL, 'DATA4');
insert into MY_TABLE (MY_COLUMN) values ('DATA5');
/
select * from MY_TABLE;