The use of SERIAL datatype is to auto increment the value, so there is no need to specify the value during insertion of values. If we create a
table and insert value to that table, by default values starts from 1 for SERIAL column datatype. But Instead of 1 is there any way to start the value from 100 and increment by 10 as default value?
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2 Answers
Serial is just syntactic sugaring on top of an int column that takes its value from a sequence. While you can't control a serial column's definitions directly, you could use an explicit sequence definition instead:
CREATE SEQUENCE tablename_colname_seq INCREMENT BY 10 START WITH 100; -- Here!
CREATE TABLE tablename (
colname integer NOT NULL DEFAULT nextval('tablename_colname_seq')
);
ALTER SEQUENCE tablename_colname_seq OWNED BY tablename.colname;
Comments
You can alter your existing sequence(not matter whether its serial or what) like below
ALTER SEQUENCE mytbl_id_seq INCREMENT 10 RESTART with 100
When creating a table
create table mytbl (id serial,val int)
a sequence will automatically creates i.e
CREATE SEQUENCE mytbl_id_seq
INCREMENT 1
START 1
so you can alter this with your desired values i.e
ALTER SEQUENCE mytbl_id_seq
INCREMENT 10
RESTART with 100
