sql sequence

[karthikpaps]

hi to everyone. Anyone can explain me about the sql sequence.

[amitpatel66]

SQL Sequencesa re basically used to generate a sequence no which can be used as a serial number in various tables.

the following code will create a sequence strart with 1

CREATE SEQUENCE seq_tmp
START WITH 1
INCREMENT BY 1
NOCACHE

Use the below queries to know the current value and the next value of the sequence:

select seq_tmp.nextval from dual -- this will give 1 when executed first time

select seq_tmp.currval from dual -- this will give 1 becuase the current value of the sequence is 1 from the above query

[debasisdas]

In oracle a SEQUENCE is used to generate a series of sequential numbers .

sample code

create sequence seqDAS
start with 50
increment by 1
minvalue 1
maxvalue 100
cycle
cache 10
order

to select the values from sequence use the Pseudo columns NEXTVAL and CURRVAL .

select seqdas.nextval from dual;
 
select seqdas.currval from dual;

[AdusumalliGopikumar]

you can view the fields of data dictionary by this

desc user_sequences

and then

select column_name1,column_name2,........., from user_sequences where sequence_name=you seqname.