Invalid Sequence name in Oracle db

Question

Recently , I am facing an issue with sequence in Oracle.

alter sequence seq_name increment by 100

will give me an error "Invalid sequence name"

However, if I changed it to

alter sequence "seq_name" increment by 100

It will work perfectly fine. Anyone is able to explain the rational behind this?

Thanks Sebastian

ps. I am using rails with oci8 to create my oracle tables.

Answer 1

Your sequence was created with case-sensitive name (using quatation marks), so you can refer to it only with strict name - in quotation marks. If you want to refer to it without such problems just create sequence not using quotation marks. Examples below (with table name):

SQL> create table "t1"(c int);

Table created.

SQL> select * from t1;
select * from t1
              *
ERROR at line 1:
ORA-00942: table or view does not exist


SQL> select * from "t1";

no rows selected

SQL> select * from "T1";
select * from "T1"
              *
ERROR at line 1:
ORA-00942: table or view does not exist


SQL> create table t2(c int);

Table created.

SQL> select * from t2;

no rows selected

SQL> select * from T2;

no rows selected

SQL> select * from "t2";
select * from "t2"
              *
ERROR at line 1:
ORA-00942: table or view does not exist


SQL> select * from "T2"; -- name without quatation marks is uppercase by default

no rows selected

Answer 2

Sequence was created as lowercase. Like this:

CREATE SEQUENCE "seq_name"  MINVALUE 1 MAXVALUE 999999999999999 INCREMENT BY 2 START WITH 1 CACHE 20 NOCYCLE  NOKEEP  NOSCALE  GLOBAL ;

Example:

select * from user_sequences where sequence_name='SEQ_NAME'; --No rows selected
select * from user_sequences where sequence_name='seq_name'; -- 1 row

If you create with name : "SEQ_name".

select * from user_sequences where sequence_name='SEQ_name'; -- 1 row

Because, when you create an object (with object name enclosed with double quotes) it will store/create as it is. Without double quotes, it would be uppercase.