oracle alter sequence by shell script & sqlplus - oracle

Question

I'm working on altering sequence through sqlplus in a shell script.
What I'm about to do is to get the max seq_no of the table, set the value in v_increment_num, and increase the sequence by v_increment_num. But it gets an error when alter statement runs.
The script is like below.
echo start load_my_adm_user.sh
sqlplus myId/myPassword <<EOF
set echo on
set time on
set timing on
set serveroutput on
spool TB_MY_ADM_USER.log
var v_increment_num varchar2(1000);
SELECT MAX(SEQ_NO) INTO :v_increment_num FROM TB_MY_ADM_USER;
alter sequence mydb.SQ_ADM_USER increment by v_increment_num;
select mydb.SQ_ADM_USER.nextval from dual;
alter sequence mydb.SQ_ADM_USER increment by 1;
spool off
EOF
exit
and the running result(TB_MY_ADM_USER.log) is like:
07:01:23 SQL> SELECT MAX(SEQ_NO) INTO :v_increment_num FROM TB_MY_ADM_USER;
MAX(SEQ_NO)
-----------
4
Elapsed: 00:00:00.00
07:01:23 SQL>
07:01:23 SQL> alter sequence mydb.SQ_ADM_USER increment by v_increment_num;
alter sequence mydb.SQ_ADM_USER increment by v_increment_num
*
ERROR at line 1:
ORA-01722: invalid number
Elapsed: 00:00:00.00
07:01:23 SQL>
07:01:23 SQL> select mydb.SQ_ADM_USER.nextval from dual;
NEXTVAL
----------
19
Elapsed: 00:00:00.02
07:01:23 SQL> alter sequence mydb.SQ_ADM_USER increment by 1;
Sequence altered.
Elapsed: 00:00:00.02
What exactly am I doing wrong?
Thanks in advance.

Answer 1

You have almost everything correct, just have to remember that DDL statements, i.e. alter sequence, too, don't work with bind variables. Which, I mean a bind variable, is what your v_increment_num is.
If SQL*Plus is what you're going to use, then try it with its own substitution "variables", i.e. the "ampersand"-variables...
echo start load_my_adm_user.sh
sqlplus myId/myPassword <<EOF
set echo on
set time on
set timing on
set serveroutput on
spool TB_MY_ADM_USER.log
-- do not do...
-- var v_increment_num varchar2(1000);
-- do instead...
column max_seq_no new_val v_increment_num
-- note: this makes all MAX_SEQ_NO column values from all subsequent SELECTs to be stored in the &V_INCREMENT_NUM variable
-- do not do...
-- SELECT MAX(SEQ_NO) INTO :v_increment_num FROM TB_MY_ADM_USER;
-- do instead...
SELECT MAX(SEQ_NO) as max_seq_no FROM TB_MY_ADM_USER;
-- note: at this point, you will have your MAX(SEQ_NO) value stored in your &V_INCREMENT_NUM variable
-- do not do...
-- alter sequence mydb.SQ_ADM_USER increment by v_increment_num;
-- do instead...
alter sequence mydb.SQ_ADM_USER increment by &v_increment_num;
select mydb.SQ_ADM_USER.nextval from dual;
alter sequence mydb.SQ_ADM_USER increment by 1;
spool off
EOF
exit
Note: I did not try this particular code, just wrote it here directly, so it may not be working at the first attempt, but we'll get that eventuality sorted out later.